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B1 noun #4,500 most common 14 min read

衛生

eisei Top 4,500

Practice it Examples Notes & Tips 衛生 in 30 Seconds

Explanation 衛生 in your Level:

At the A1 level, you don't need to use the word '衛生' (eisei) very often, but you will see it on signs and in stores. Think of it as a fancy word for 'clean' or 'doctor-clean.' When you see '衛生' on a bottle in a drugstore, it means it is a product for staying clean and healthy, like a mask or hand soap. At this stage, you should focus on the basic idea: 'Eisei' equals 'clean for health.' You might hear a teacher say 'Wash your hands for hygiene,' but you can just remember that it's related to the word 'clean' (きれい, kirei). You won't be expected to use it in your own sentences yet, but recognizing it on a sign in a bathroom or a hospital is a great first step. Just remember: Ei (protect) + Sei (life). It's the word used to keep people from getting sick. If you see '衛生' and a picture of hands, it means 'wash your hands!'

At the A2 level, you can start to recognize '衛生' (eisei) as a noun that describes the 'state' of cleanliness. You might use it to talk about basic habits. For example, you can say 'Eisei wa taisetsu desu' (Hygiene is important). You will encounter this word in school settings or at work if you are in Japan. It is the word used for the school nurse's office topics. You should know that 'eisei' is more formal than 'kirei.' If you are at a restaurant and see a sign about 'eisei,' it's about the rules for the kitchen. You might also see 'eisei-yōhin' (hygiene products) in a supermarket. Try to remember that when you want to sound a bit more serious about health and germs, 'eisei' is the word to use. It is a common word in announcements during flu season. 'Please take care of your hygiene' is a common phrase you will hear on the train or at school.

At the B1 level, you should be able to use '衛生' (eisei) in more specific contexts, especially in compound words. You are expected to understand terms like '衛生管理' (hygiene management) and '衛生状態' (sanitary conditions). If you are working in Japan, particularly in food service or healthcare, this word is essential. You should be able to explain why hygiene is important using the grammar 'eiseijō' (for hygiene reasons). For example, 'Eiseijō, koko de kutsu wo nuide kudasai' (For hygiene reasons, please take off your shoes here). You should also be aware of the phrase '精神衛生' (mental hygiene) and understand that it refers to your peace of mind. At this level, you are moving beyond just 'cleaning' and starting to talk about 'sanitation' as a social and professional standard. You can participate in discussions about public health or workplace safety using this term correctly.

At the B2 level, you should use '衛生' (eisei) with precision in professional and academic discussions. You should be comfortable with terms like '公衆衛生' (public health) and '環境衛生' (environmental hygiene). You can discuss the differences between '衛生' (prevention) and '治療' (treatment). You should also be able to use the adjective form '衛生的' (eiseiteki) to describe facilities or practices. For example, you might critique a facility by saying its 'eisei jōtai' is below standard. You will likely encounter this word in newspaper articles about the environment, international aid, or medical breakthroughs. You should also be able to distinguish 'eisei' from its homophone 'eisei' (satellite) based on context and kanji. Your ability to use 'eisei' in various compounds shows a high level of vocabulary integration and cultural understanding of Japan's health standards.

At the C1 level, you have a deep understanding of the historical and social nuances of '衛生' (eisei). You can discuss how the concept of 'Eisei' was a pillar of Japan's modernization during the Meiji period and how it shifted the cultural focus from religious purity to scientific sanitation. You are capable of reading technical documents, such as the 'Food Sanitation Act' (食品衛生法), and understanding the legal implications of 'eisei' standards. You can use the word in abstract or metaphorical ways, particularly '精神衛生' (mental hygiene), to discuss complex psychological states or social environments. You can also engage in high-level debates about global 'eisei' issues, such as water scarcity or the impact of urban density on public health. Your usage is indistinguishable from a native speaker, showing sensitivity to register and the specific technical domains where 'eisei' is the preferred term over more common words.

At the C2 level, you possess a masterly command of '衛生' (eisei) and its place in the Japanese lexicon. You can analyze the word's role in the development of the Japanese welfare state and its intersection with concepts of 'shitsuke' (discipline) and 'public morality.' You are able to interpret and produce complex texts on epidemiology, sanitary engineering, or medical history where 'eisei' is a central theme. You understand the subtle differences in how 'eisei' is used across different professional fields—from combat medics (衛生兵) to dental hygienists (歯科衛生士). You can also appreciate the word's appearance in literature or historical archives, understanding the weight it carried during periods of epidemic or war. Your ability to manipulate the word in various grammatical structures, including rare or archaic compounds, demonstrates a profound linguistic and cultural fluency that encompasses the entirety of the word's historical and modern usage.

Practice it Examples Notes & Tips

衛生 in 30 Seconds

衛生 (eisei) translates to 'hygiene' or 'sanitation' and focus on disease prevention.
It is a formal noun often used in professional, medical, and industrial contexts.
The word is composed of kanji meaning 'protect' and 'life,' highlighting its core purpose.
Common compounds include public health, food hygiene, and mental hygiene (peace of mind).

The Japanese word 衛生 (えいせい, eisei) is a profound term that translates to 'hygiene' or 'sanitation' in English, but its etymological roots provide a deeper insight into its significance. Composed of the kanji 衛 (guard/protect) and 生 (life), it literally means 'protecting life.' This concept emerged prominently during the Meiji era as Japan modernized its medical and social systems, adopting Western concepts of public health. While in English, 'hygiene' might evoke personal habits like brushing teeth, in Japanese, 衛生 often carries a more systemic, institutional, or scientific weight, referring to the conditions and practices that prevent disease and maintain health on a broad scale.

Public Health Context: In the realm of governance and science, 公衆衛生 (kōshū eisei) refers to public health. This includes everything from waste management and water purification to vaccination programs and pandemic control. When you hear this word on the news, it is usually regarding government policies or scientific findings.
Food and Safety: In the food industry, 食品衛生 (shokuhin eisei) is a critical term. It refers to food safety standards. Restaurants must adhere to strict hygiene laws to prevent food poisoning. A 'Food Hygiene Manager' (shokuhin eisei sekininsha) is a required role in Japanese eateries.
Mental Well-being: Interestingly, the word is also used for mental health in the phrase 精神衛生 (seishin eisei). This refers to the 'hygiene of the mind,' or practices that keep one's psychological state healthy and balanced, such as avoiding toxic environments or managing stress.

レストランの厨房では、厳格な衛生管理が求められます。 (In restaurant kitchens, strict hygiene management is required.)

The usage of 衛生 is ubiquitous in Japan, a country known for its high standards of cleanliness. From the meticulous cleaning of trains to the common practice of wearing masks even before the global pandemic, the concept of 'protecting life' through cleanliness is woven into the social fabric. It is not just about being 'clean' (清潔, seiketsu), which can be aesthetic; 衛生 is about being 'sanitary,' which is biological and preventative. Therefore, the word appears frequently in medical, industrial, and educational settings.

この地域は衛生状態が非常に良い。 (The sanitary conditions in this area are very good.)

Furthermore, 衛生 is often paired with other nouns to create specific terms. For example, 衛生兵 (eiseihei) refers to a combat medic, someone who 'protects life' on the battlefield. 衛生用品 (eiseiyōhin) refers to sanitary products, including masks, hand sanitizers, and feminine hygiene products. This versatility shows that the word covers everything from basic survival to high-level public policy. In a Japanese school, the student council might have a 'Hygiene Committee' (eisei-iinkai) responsible for ensuring soap is stocked and classrooms are aired out.

Environmental Hygiene: 環境衛生 (kankyō eisei) deals with the health of the surroundings, such as air quality, noise pollution, and waste disposal. It is a common topic in urban planning.
Oral Hygiene: 口腔衛生 (kōkū eisei) is the clinical term for dental/oral hygiene. You will see this at the dentist's office rather than 'brushing teeth' (歯磨き).

手洗いは最も基本的な衛生習慣の一つです。 (Hand washing is one of the most basic hygiene habits.)

災害時には、避難所の衛生を保つことが不可欠です。 (In times of disaster, it is essential to maintain hygiene in evacuation centers.)

彼女は衛生学を専攻している。 (She is majoring in hygiene/sanitary science.)

In summary, 衛生 is not just about looking clean; it is about the structural and behavioral systems that protect biological life. Whether you are reading a menu, a government report, or a medical pamphlet, understanding this word is key to navigating the high-standards of health and safety in Japanese society.

Using 衛生 (えいせい) correctly involves understanding its role as a noun that often acts as a modifier for other nouns. While it is a noun, it rarely functions as a standalone subject in casual speech; instead, it frequently appears in compound phrases or is followed by particles like no (の) or verbs like wo tamotsu (を保つ - to maintain). Here we will explore the grammatical patterns and common combinations that will make your Japanese sound more natural and professional.

Maintaining Hygiene: The most common verb paired with 衛生 is 保つ (tamotsu), meaning 'to keep' or 'to maintain.' This is used in contexts like hospitals, kitchens, or personal spaces. Example: Eisei wo tamotsu koto wa jūyō desu (Maintaining hygiene is important).
Hygiene Management: The compound 衛生管理 (eisei kanri) is a staple in business and industry. It refers to the management of sanitary conditions. You will see signs in workplaces saying Eisei kanri tettei (Thorough hygiene management).
Sanitary Conditions: To describe the state of a place, use 衛生状態 (eisei jōtai). You can say it is yoi (good) or warui (bad). This is often used when discussing developing countries, disaster zones, or neglected properties.

キャンプ場では、個人の衛生に気をつけてください。 (Please be careful about personal hygiene at the campsite.)

When used with the particle jō (上), as in 衛生上 (eiseijō), it means 'from a hygiene standpoint' or 'for sanitary reasons.' This is a very common way to explain rules or prohibitions. For example, 'For hygiene reasons, pets are not allowed' would be Eiseijō, petto wa kinshi desu. This structure is concise and formal.

生ものを扱うときは、衛生面に細心の注意を払う必要があります。 (When handling raw food, it is necessary to pay close attention to the hygiene aspect.)

In academic or medical writing, 衛生 is often used to categorize branches of science. 衛生学 (eiseigaku) is the study of hygiene or sanitary science. If you are talking about someone's profession, you might use 歯科衛生士 (shika eiseishi), which is the specific title for a dental hygienist. These terms are fixed and should be learned as single units of meaning.

Bad for Mental Health: A unique psychological use is 精神衛生に悪い (seishin eisei ni warui). This is a common idiomatic expression meaning something is 'bad for one's peace of mind' or 'mentally unhealthy.' For example, reading hateful comments online is seishin eisei ni warui.
Public Health Facilities: 衛生施設 (eisei shisetsu) refers to sanitary facilities like toilets, washrooms, and sewage treatment plants. This term is common in international development and urban engineering.

この古いアパートは衛生基準を満たしていません。 (This old apartment does not meet hygiene standards.)

学校の衛生委員会が石鹸を補充しました。 (The school's hygiene committee refilled the soap.)

When discussing international issues, you might encounter 世界保健機関 (Sekai Hoken Kikan), the WHO. While 'hoken' (health) is used in the title, their reports are filled with the word 衛生 when discussing water and sanitation (WASH). In this context, 衛生 is a technical indicator of social development. In your own writing, using 衛生 instead of 清潔 will immediately elevate the register of your Japanese to a more professional or academic level.

SNSの使いすぎは精神衛生上、良くない。 (Overusing social media is not good from a mental hygiene standpoint.)

To master 衛生, focus on the compounds. It is rarely the 'star' of a sentence but rather the 'qualifier' that defines the context of health and safety. Whether you are talking about a messy room or a global virus, 衛生 provides the scientific framework for the discussion.

In Japan, you will encounter the word 衛生 (えいせい) in a variety of real-world settings, ranging from the mundane to the highly specialized. Japan's cultural emphasis on cleanliness means that hygiene is a constant topic of public discourse. Understanding where this word pops up will help you navigate daily life, from reading signs in a public restroom to understanding news reports on public safety.

In Schools (Hoken-shitsu): Every Japanese school has a health room or infirmary called the 保健室 (hoken-shitsu). The school nurse often gives talks on 衛生, teaching children about 'hand-washing and gargling' (tearai-ugai). You'll see posters titled 衛生だより (Eisei Dayori), which is a 'Hygiene Newsletter' sent home to parents to warn about flu season or lice.
At Restaurants and Cafes: If you work in a Japanese kitchen, 衛生 will be the word you hear most often from your manager. 'Hygiene inspection' (衛生検査) is a stressful time for restaurant owners. You will see stickers on the wall indicating that the establishment has passed its 食品衛生 (shokuhin eisei) checks.
In the News and Media: During any health crisis, such as an influenza outbreak or the COVID-19 pandemic, news anchors constantly use terms like 公衆衛生 (kōshū eisei). They discuss the 衛生環境 (eisei kankyō) of crowded places and the importance of 個人衛生 (kojin eisei) (personal hygiene).

本日は衛生検査のため、営業時間を短縮します。 (Today, we will shorten our business hours for a hygiene inspection.)

You will also see the word in retail. The 'sanitary products' aisle in a drugstore is labeled 衛生用品 (eiseiyōhin). This is where you find bandages, alcohol wipes, masks, and thermometers. It is a useful word to know if you are feeling unwell and need to ask a clerk for help: 'Where are the hygiene products?' (Eiseiyōhin wa doko desu ka?).

ドラッグストアで衛生用品を買いだめした。 (I stocked up on hygiene products at the drugstore.)

In the workplace, especially in manufacturing or medical fields, the morning assembly (chōreai) might include a reminder about 衛生管理 (eisei kanri). This isn't just a suggestion; it's a protocol. In factories, you'll see the slogan '5S' (Seiri, Seiton, Seisō, Seiketsu, Shitsuke), where Seiketsu (Cleanliness) is often explained through the lens of 衛生.

At the Dentist: When you get your teeth cleaned, the person doing the work is usually a 歯科衛生士 (shika eiseishi). They will give you advice on 口腔衛生 (kōkū eisei), or oral hygiene. You will see this word on pamphlets about cavities and gum disease.
Public Restrooms: Signs in public restrooms often say 衛生的に使用しましょう (Eiseiteki ni shiyō shimashō), meaning 'Let's use this facility in a sanitary manner.' This is a polite way of asking people to keep the area clean for the next person.

彼は衛生士の資格を取るために勉強している。 (He is studying to get a hygienist qualification.)

都会の衛生問題は深刻だ。 (Sanitary issues in the city are serious.)

Finally, in the world of space exploration, you might hear a homophone: 衛星 (eisei), which means 'satellite.' While the sound is identical, the kanji are different (衛 + 星 vs 衛 + 生). Context usually makes it clear, but if someone is talking about 'hygiene' in space, they are likely talking about 衛生 (sanitation) aboard the 衛星 (satellite) or space station!

While 衛生 (えいせい) is a straightforward word, English speakers often encounter a few pitfalls when trying to use it in Japanese. The most common issues arise from confusing it with related words like 'clean' or 'health,' or from misidentifying its homophones. Understanding these nuances will prevent you from sounding awkward or overly technical in the wrong situations.

Confusing 衛生 with 清潔 (Seiketsu): This is the most frequent mistake. 清潔 means 'cleanliness' or 'neatness' in a visual and personal sense. 衛生 means 'hygiene' or 'sanitation' in a biological and systemic sense. If your room is messy, it's not a 'hygiene' problem (usually); it's a 'cleanliness' problem. Use 衛生 when bacteria, viruses, or health risks are involved.
The Homophone Trap: 衛星 (Satellite): As mentioned before, 衛星 (satellite) and 衛生 (hygiene) are pronounced exactly the same: eisei. When typing on a Japanese keyboard, be careful to select the correct kanji. Choosing 'satellite' when you mean 'hygiene' in a message to a doctor would be quite confusing!
Overuse in Casual Settings: Using 衛生 in a casual conversation with friends can sound a bit like a textbook or a government official. Instead of saying 'Your hygiene is bad,' which sounds like a medical diagnosis, people usually say kitanai (dirty) or fuketsū (unclean).

❌ この部屋は衛生だ。 (This room is hygiene.)
✅ この部屋は清潔だ。 (This room is clean.)

Another mistake is the grammar of 衛生. It is a noun, not an adjective. You cannot say eisei na mise (a hygiene restaurant). You must say 衛生的な店 (eiseiteki na mise), using the suffix -teki to turn the noun into a 'na-adjective' meaning 'hygienic.' This is a very common grammatical error for learners who assume nouns can be used directly as adjectives.

❌ 衛生を洗う。 (Wash hygiene.)
✅ 手を洗って、衛生を保つ。 (Wash hands and maintain hygiene.)

Misunderstanding 精神衛生 (seishin eisei) is also common. Some learners think it refers to 'brain health' or 'neurology.' In reality, it is much closer to 'mental health' or 'mental well-being.' If you say something is 'bad for your mental hygiene,' you are saying it's stressing you out or making you unhappy, not that you have a medical disease.

Confusing with 健康 (Kenkō): 健康 is 'health' (the state of the body). 衛生 is 'hygiene' (the practices to stay healthy). You don't 'eat hygiene' to stay healthy; you eat 'healthy food' (kenkōteki na shokuji). You maintain 衛生 to avoid getting sick.
Incorrect Particle Use: Don't say Eisei ni suru to mean 'to make it hygienic.' Use 衛生的（えいせいてき）にする or 衛生を改善（かいぜん）する (improve hygiene).

❌ この水は衛生ではない。 (This water is not hygiene.)
✅ この水は衛生的ではない。 (This water is not hygienic.)

By being mindful of these distinctions—especially the difference between 'clean' (visual) and 'hygienic' (biological)—you will use 衛生 with the precision of a native speaker. Pay attention to the suffixes like -teki and -jō, as they are the keys to unlocking the word's full potential in sentence structures.

To truly master 衛生 (えいせい), it is helpful to compare it with other Japanese words that deal with cleanliness, health, and safety. While English might use 'clean' or 'healthy' in many situations, Japanese has specific terms that distinguish between aesthetic cleanliness, medical sterilization, and general well-being. Here is a breakdown of the most common alternatives and how they differ from 衛生.

清潔 (Seiketsu) vs. 衛生 (Eisei): 清潔 focuses on being clean, pure, and free of dirt or clutter. It is often used for personal appearance or the look of a room. 衛生 is scientific and preventative. A room can look 清潔 but not be 衛生的 (e.g., it looks tidy but has bacteria on the surfaces).
健康 (Kenkō) vs. 衛生 (Eisei): 健康 is the state of health itself. 'I am healthy' is Kenkō desu. 衛生 is the infrastructure or habit that supports health. You don't say 'I am hygiene.' You say 'I practice good hygiene to stay healthy.'
消毒 (Shōdoku) vs. 衛生 (Eisei): 消毒 means 'disinfection' or 'sterilization.' This is an action you take. 衛生 is the overall condition. You perform 消毒 to maintain 衛生.

病院では衛生管理のために、器具の消毒を徹底している。 (In hospitals, for hygiene management, they are thorough in disinfecting instruments.)

Another word often confused is 不潔 (fuketsu), which is the antonym of 清潔. It means 'filthy' or 'unclean.' While you could say a place has 'poor hygiene' (eisei jōtai ga warui), calling it 不潔 is a much more visceral, negative judgment about the lack of cleanliness. 不潔 can also be used figuratively to mean 'immoral' or 'sleazy,' whereas 衛生 is never used this way.

彼はとても清潔感のある人だ。 (He is a person who gives off a great sense of cleanliness/neatness.)

In formal settings, you might also hear 保健 (hoken). While 衛生 refers to sanitation, 保健 refers to health preservation or preservation of health. The 'Ministry of Health, Labour and Welfare' is Kōsei Rōdō Shō, but it oversees both 衛生 and 保健. Generally, 衛生 is the 'clean' side of health, while 保健 is the 'wellness' side.

除菌 (Jokin): This means 'removal of bacteria.' You see this on soap bottles and wet wipes. It is a more specific, marketing-friendly term than the academic-sounding 衛生.
安全 (Anzen): Sometimes 衛生 is used interchangeably with 'safety' in contexts like 安全衛生 (anzen eisei) - health and safety at work. Here, it refers to preventing injury and illness.

工場の安全衛生教育に参加した。 (I participated in the factory's safety and health education.)

In summary, 衛生 is your 'scientific' word for sanitation. Use 清潔 for 'looks clean,' 健康 for 'feels healthy,' and 消毒 for the act of 'killing germs.' By choosing the right word, you show a sophisticated understanding of Japanese social and professional standards.

How Formal Is It?

Fun Fact

Before 'Eisei' was coined, there was no single word for public health in Japan. Nagayo Sensai found the term in a classic Chinese text (Zhuangzi), where it referred to 'taking care of one's health,' and repurposed it for modern medicine.

Pronunciation Guide

UK /eɪˈseɪ/

US /eɪˈseɪ/

Japanese pitch accent is 'Heiban' (Flat). The pitch starts low and stays high throughout the word: e-i-se-i.

Difficulty Rating

Reading 3/5

The kanji '衛' is somewhat complex but very common in medical and safety contexts.

Writing 4/5

Writing '衛' requires 16 strokes and correct stroke order to look balanced.

Speaking 2/5

Pronunciation is simple, but the homophone 'eisei' (satellite) requires context.

Listening 3/5

Must distinguish from 'satellite' and 'eternity' (eisei - slightly different pitch).

What to Learn Next

Prerequisites

健康 (Health) 清潔 (Clean) 生活 (Life/Lifestyle) 管理 (Management) 病院 (Hospital)

Learn Next

予防 (Prevention) 感染 (Infection) 免疫 (Immunity) 医療 (Medical care) 環境 (Environment)

Advanced

公衆衛生学 (Public health science) 疫学 (Epidemiology) 滅菌 (Sterilization) バイオハザード (Biohazard) 厚生労働省 (Ministry of Health, Labour and Welfare)

Grammar to Know

Noun + 上 (jō)

衛生上の理由で (For hygiene reasons)

Noun + 的 (teki)

衛生的な環境 (A hygienic environment)

Noun + 面 (men)

衛生面を考慮する (Consider the hygiene aspect)

Compound Nouns (Kango)

食品衛生責任者 (Food hygiene manager)

Suru-verbs with compounds

衛生管理する (To manage hygiene)

Examples by Level

衛生のために、手を洗いましょう。

For hygiene, let's wash our hands.

衛生 (eisei) is used with 'no tame ni' (for the sake of).

ここは衛生的なトイレです。

This is a hygienic toilet.

衛生的 (eiseiteki) is the adjective form.

衛生用品はどこですか？

Where are the hygiene products?

衛生用品 (eiseiyōhin) is a compound noun.

レストランは衛生が大切です。

Hygiene is important for restaurants.

衛生 (eisei) is the subject here.

学校で衛生について習いました。

I learned about hygiene at school.

衛生 (eisei) is followed by 'ni tsuite' (about).

この水は衛生上、飲めません。

From a hygiene standpoint, you cannot drink this water.

衛生上 (eiseijō) means 'regarding hygiene'.

毎日お風呂に入るのは衛生にいいです。

Taking a bath every day is good for hygiene.

衛生にいい (eisei ni ii) means 'good for hygiene'.

きれいな服は衛生の基本です。

Clean clothes are the basis of hygiene.

衛生の基本 (eisei no kihon) means 'basis of hygiene'.

キャンプ場では、衛生に気をつけてください。

Please be careful about hygiene at the campsite.

衛生に気をつける (eisei ni ki wo tsukeru) means 'to be careful about hygiene'.

この店は衛生管理がしっかりしています。

This shop's hygiene management is solid.

衛生管理 (eisei kanri) is 'hygiene management'.

不衛生な場所には行かないでください。

Please do not go to unhygienic places.

不衛生 (fueisei) is the antonym, meaning 'unhygienic'.

歯科衛生士さんに歯を磨いてもらいました。

I had my teeth cleaned by a dental hygienist.

歯科衛生士 (shika eiseishi) is 'dental hygienist'.

冬は衛生面に注意が必要です。

In winter, attention to hygiene is necessary.

衛生面 (eiseimen) means 'the hygiene aspect'.

台所を衛生的に保ちましょう。

Let's keep the kitchen hygienic.

衛生的に保つ (eiseiteki ni tamotsu) means 'to keep hygienically'.

この薬は衛生的な工場で作られています。

This medicine is made in a hygienic factory.

衛生的 (eiseiteki) modifies 'factory'.

災害の後は衛生状態が悪くなりやすいです。

After a disaster, sanitary conditions tend to worsen.

衛生状態 (eisei jōtai) means 'sanitary conditions'.

食品衛生責任者の資格を取りました。

I obtained the qualification of food hygiene manager.

食品衛生責任者 (shokuhin eisei sekininsha) is a specific title.

過度なストレスは精神衛生に良くありません。

Excessive stress is not good for mental hygiene.

精神衛生 (seishin eisei) refers to mental well-being.

公共の場所では、公衆衛生を守る義務があります。

In public places, there is an obligation to maintain public health.

公衆衛生 (kōshū eisei) means 'public health'.

この地域は、衛生施設が整っています。

This area has well-equipped sanitary facilities.

衛生施設 (eisei shisetsu) refers to sanitary infrastructure.

衛生上の理由から、ペットの同伴はご遠慮ください。

For hygiene reasons, please refrain from bringing pets.

衛生上の理由 (eiseijō no riyū) is a formal way to say 'for hygiene reasons'.

彼は衛生学の講義を受けています。

He is taking a lecture on hygiene/sanitary science.

衛生学 (eiseigaku) is the study of hygiene.

避難所での衛生を保つために、ボランティアが掃除をしました。

To maintain hygiene in the shelter, volunteers did the cleaning.

衛生を保つ (eisei wo tamotsu) is a standard phrase.

この化粧品は衛生面に配慮して個包装されています。

These cosmetics are individually wrapped with hygiene in mind.

衛生面に配慮する (eiseimen ni hairyo suru) means 'considering hygiene'.

途上国の衛生環境を改善するためのプロジェクトが進行中です。

A project is underway to improve the sanitary environment in developing countries.

衛生環境 (eisei kankyō) refers to the overall sanitary environment.

この工場は、国際的な衛生基準をクリアしています。

This factory has cleared international hygiene standards.

衛生基準 (eisei kijun) means 'hygiene standards'.

精神衛生を保つために、デジタルデトックスを始めました。

In order to maintain mental hygiene, I started a digital detox.

精神衛生を保つ (seishin eisei wo tamotsu) is used here for mental health.

食品の衛生検査が厳格化されました。

Hygiene inspections for food have been tightened.

衛生検査 (eisei kensa) means 'hygiene inspection'.

環境衛生の観点から、プラスチック削減が求められています。

From the viewpoint of environmental hygiene, plastic reduction is required.

衛生の観点 (eisei no kanten) means 'from the perspective of hygiene'.

労働衛生コンサルタントに相談することにしました。

I decided to consult with an industrial health and safety consultant.

労働衛生 (rōdō eisei) is 'industrial/occupational health'.

都市部における公衆衛生の歴史を研究しています。

I am researching the history of public health in urban areas.

公衆衛生の歴史 (kōshū eisei no rekishi) is a research topic.

衛生局が新しい感染症への対策を発表しました。

The Department of Health announced measures against a new infectious disease.

衛生局 (eiseikyoku) is the 'Bureau of Health/Hygiene'.

明治政府は、近代化の一環として衛生行政の整備を急いだ。

The Meiji government hurried the development of hygiene administration as part of modernization.

衛生行政 (eisei gyōsei) refers to 'hygiene administration'.

SNS上の誹謗中傷は、社会全体の精神衛生を著しく損なう。

Slander on social media significantly damages the mental hygiene of society as a whole.

精神衛生を損なう (seishin eisei wo sokonau) means 'to damage mental hygiene'.

その論文は、発展途上国における口腔衛生の格差を指摘している。

The paper points out the gap in oral hygiene in developing countries.

口腔衛生 (kōkū eisei) is the formal term for oral hygiene.

彼は衛生兵としての過酷な経験を自伝に綴った。

He wrote about his harsh experiences as a combat medic in his autobiography.

衛生兵 (eiseihei) is a combat medic.

バイオテクノロジーの進歩が、新たな公衆衛生上の課題を生んでいる。

Advancements in biotechnology are creating new public health challenges.

公衆衛生上の課題 (kōshū eiseijō no kadai) is a 'public health challenge'.

衛生陶器の需要は、都市のインフラ整備に直結している。

The demand for sanitary ceramics (toilets, etc.) is directly linked to urban infrastructure development.

衛生陶器 (eisei tōki) is the technical term for sanitary ware.

感染症の蔓延を防ぐには、衛生思想の普及が不可欠だ。

To prevent the spread of infectious diseases, the dissemination of hygiene ideology is essential.

衛生思想 (eisei shisō) refers to 'concepts/ideology of hygiene'.

その工場は、労働安全衛生法に抵触する恐れがある。

The factory is at risk of violating the Industrial Safety and Health Act.

労働安全衛生法 (Rōdō Anzen Eisei Hō) is a specific law.

フーコーの生政治学の観点から、衛生という概念を再考する。

Reconsidering the concept of hygiene from the perspective of Foucault's biopolitics.

衛生という概念 (eisei to iu gainen) means 'the concept known as hygiene'.

パンデミックの最中、公衆衛生と個人の自由の相克が浮き彫りになった。

During the pandemic, the conflict between public health and individual liberty became starkly apparent.

相克 (sōkoku) means 'conflict/rivalry'.

衛生環境の劇的な改善が、日本の平均寿命の伸長に寄与したことは疑いようがない。

There is no doubt that the dramatic improvement in the sanitary environment contributed to the extension of Japan's average life expectancy.

伸長に寄与する (shinchō ni kiyo suru) means 'contribute to the extension'.

宇宙ステーション内での衛生維持は、閉鎖系における極めて複雑な課題である。

Maintaining hygiene within a space station is an extremely complex challenge in a closed system.

衛生維持 (eisei iji) means 'maintenance of hygiene'.

精神衛生という言葉が、かつては優生学的な文脈で使われていた歴史を忘れてはならない。

We must not forget the history where the term 'mental hygiene' was once used in a eugenics context.

優生学的な文脈 (yūseigakuteki na bunmyaku) means 'eugenics context'.

水質汚染が深刻化する中、環境衛生学の役割はますます重要性を増している。

As water pollution worsens, the role of environmental health science is becoming increasingly important.

重要性を増す (jūyōsei wo masu) means 'increase in importance'.

都市計画において、衛生陶器の配置と下水道網の整備は不可分である。

In urban planning, the placement of sanitary ware and the development of the sewer network are inseparable.

不可分 (fukabun) means 'inseparable'.

彼は、戦時下における衛生兵の倫理的ジレンマについて論文を執筆した。

He wrote a paper on the ethical dilemmas of combat medics during wartime.

倫理的ジレンマ (rinriteki jirenma) means 'ethical dilemma'.

Common Collocations

衛生管理

衛生状態

衛生用品

公衆衛生

精神衛生

歯科衛生士

衛生基準

衛生検査

口腔衛生

環境衛生

Common Phrases

衛生を保つ

— To maintain hygiene. Used in both personal and professional contexts.

常に衛生を保つことが大切です。

衛生上の理由

— For hygiene reasons. A common formal explanation for rules or bans.

衛生上の理由により、立入禁止です。

精神衛生に悪い

— Bad for mental hygiene. Used when something is stressful or mentally taxing.

そのニュースを見るのは精神衛生に悪い。

衛生管理の徹底

— Thorough hygiene management. A common slogan in Japanese workplaces.

工場内では衛生管理の徹底をお願いします。

衛生面に配慮する

— To consider the hygiene aspect. Used when planning events or products.

衛生面に配慮したパッケージデザイン。

衛生状態の悪化

— Worsening of sanitary conditions. Used in news about disasters or war.

被災地では衛生状態の悪化が懸念されている。

衛生的な生活

— A hygienic life. Refers to living in a way that prevents illness.

衛生的で健康な生活を送る。

衛生局の指導

— Guidance from the health bureau. Used in business contexts.

衛生局の指導に従って改善する。

個人衛生の確立

— Establishment of personal hygiene. A formal way to talk about developing habits.

子供たちに個人衛生の確立を促す。

衛生思想の普及

— Spread of hygiene ideology. A historical or sociological term.

明治時代に衛生思想の普及が進んだ。

Often Confused With

衛生 vs 清潔 (Seiketsu)

English speakers use 'clean' for both. In Japanese, Seiketsu is visual/personal, Eisei is biological/systemic.

衛生 vs 健康 (Kenkō)

Kenkō is the state of being healthy. Eisei is the practice of maintaining it.

衛生 vs 衛星 (Eisei)

Same pronunciation, but means 'satellite.' Check kanji carefully.

Idioms & Expressions

"精神衛生を保つ"

— To keep one's peace of mind or stay mentally healthy.

趣味の時間は、精神衛生を保つために必要だ。

Neutral

"衛生を重んじる"

— To place high value on hygiene.

日本人は古くから衛生を重んじる国民性がある。

Formal

"衛生の盲点"

— A blind spot in hygiene. Refers to a place or habit that is overlooked.

スマートフォンの画面は、衛生の盲点になりやすい。

Neutral

"衛生上の配慮"

— Consideration for hygiene purposes.

衛生上の配慮から、手袋を着用しています。

Formal

"不衛生の極み"

— The height of unhygienic conditions; extremely filthy.

その放置されたゴミ山は、不衛生の極みだった。

Informal/Emphatic

"衛生の鑑"

— A model of hygiene. Someone or something that is perfectly sanitary.

彼の整理整頓されたデスクは、職場の衛生の鑑だ。

Literary

"衛生面に抜かりがない"

— To have no oversight in terms of hygiene; to be flawless.

そのホテルの客室清掃は、衛生面に抜かりがない。

Neutral

"衛生が命"

— Hygiene is life (paramount). Used by restaurant owners or doctors.

この仕事は衛生が命ですから、妥協は許されません。

Informal/Passionate

"精神衛生上の問題"

— A problem concerning mental hygiene/well-being.

職場いじめは深刻な精神衛生上の問題だ。

Formal

"衛生を害する"

— To harm or compromise hygiene.

不法投棄は地域の衛生を害する行為だ。

Formal

Easily Confused

衛生 vs 永世 (Eisei)

Same pronunciation.

Means 'eternity' or 'permanent.' Used in titles like 'Eisei Meijin' in Shogi.

彼は永世名人の称号を得た。

衛生 vs 鋭製 (Eisei - hypothetical)

Phonetic similarity.

Not a common word, but might be confused by learners creating compounds.

N/A

衛生 vs 保健 (Hoken)

Both relate to health.

Hoken is 'health preservation' (wellness/insurance), Eisei is 'sanitation' (cleaning/germs).

保健の授業を受ける。

衛生 vs 防疫 (Bōeki)

Both involve preventing disease.

Bōeki is specifically about stopping the spread of epidemics/infections.

空港で防疫体制を整える。

衛生 vs 洗浄 (Senjō)

Both relate to cleaning.

Senjō is the technical act of washing or flushing something out.

部品の洗浄を行う。

Sentence Patterns

[Place] は [衛生] が大切です。

病院は衛生が大切です。

[衛生] に気をつける。

毎日の衛生に気をつける。

[衛生] 上の理由で [Action]。

衛生上の理由で、中に入れません。

[精神衛生] に [悪い/良い]。

散歩は精神衛生に良い。

[衛生管理] を徹底する。

厨房の衛生管理を徹底する。

[衛生状態] が [改善/悪化] する。

衛生状態が劇的に改善した。

[衛生] の観点から [Argument]。

公衆衛生の観点から、その政策を支持する。

[衛生] という概念の [変遷/歴史]。

近代における衛生という概念の変遷を辿る。

Word Family

Nouns

公衆衛生 (Public health)

食品衛生 (Food hygiene)

精神衛生 (Mental hygiene)

環境衛生 (Environmental hygiene)

Verbs

衛生管理する (To manage hygiene - though usually a noun + verb structure)

Adjectives

衛生的 (Hygienic)

不衛生 (Unhygienic)

清潔 (Cleanliness)

健康 (Health)

消毒 (Disinfection)

除菌 (Bacteria removal)

保健 (Health preservation)

How to Use It

frequency

Highly frequent in professional, medical, and news contexts. Moderately frequent in daily life signs.

Common Mistakes

Using 衛生 as a na-adjective without '-teki'. → 衛生的 (eiseiteki)
衛生 is a noun. You cannot say 'eisei na mise.' You must say 'eiseiteki na mise.'
Confusing 衛生 (Hygiene) with 衛星 (Satellite). → 衛生
In writing, using 'star' (星) instead of 'life' (生) changes the meaning completely.
Using 衛生 for 'neatness' or 'tidiness'. → 清潔 (Seiketsu) or 整理整頓 (Seiri Seiton)
If the room is just messy (books on the floor), it's not a hygiene issue. Hygiene involves germs and health risks.
Saying 衛生をする (To do hygiene). → 衛生を保つ (To maintain hygiene) or 衛生管理をする (To manage hygiene).
衛生 is not an action you 'do' like 'cooking.' It's a state you maintain or a field you manage.
Confusing 衛生 with 健康. → 健康 (Kenkō)
Don't say 'I eat hygiene food.' Say 'I eat healthy food' (kenkōteki na shokuji).

Tips

Use with '-teki'

Remember that 衛生 is a noun. To describe something as hygienic, you must add '-teki' to make it '衛生的' (eiseiteki). This is a common mistake for beginners.

School Cleaning

In Japan, cleaning (Soji) is part of the curriculum. This is seen as a way to teach 'Eisei' and social responsibility from a young age.

Stroke Order of 衛

The kanji 衛 is complex. Focus on the center part first, then the 'walk' radical on the left and the right side. It takes practice to write it neatly.

Mental Hygiene

The phrase 精神衛生 (seishin eisei) is very useful. Use it to talk about things that stress you out or things that help you relax, like 'This hobby is good for my mental hygiene.'

Flat Pitch

Keep your voice level when saying 'eisei.' If you drop the pitch at the end, it might sound like a different word or just unnatural.

Workplace Safety

If you work in a Japanese company, look for the '安全衛生' (Anzen Eisei) posters. They contain important safety and health information.

Finding Products

In a drugstore, look for the sign '衛生用品' (Eiseiyōhin). This is where you will find masks, bandages, and disinfectants.

Context Clues

When you see 'eisei' in a news headline, look at the surrounding kanji. '食品' (food) or '公衆' (public) will tell you exactly what kind of hygiene is being discussed.

Formal Reasons

If you need to give a formal reason why something isn't allowed (like no shoes or no food), '衛生上の理由' (eiseijō no riyū) is the perfect, polite phrase.

The Medic Connection

If you play video games or watch anime, remember 'Eisei-hei' (Medic). They guard life. This will help you remember the 'Ei' and 'Sei' kanji together.

Memorize It

Mnemonic

Think of an 'Ace' (Ei) student who 'Saves' (Sei) lives. An Ace student saves life through good hygiene.

Visual Association

Imagine a shield (guarding/Ei) protecting a small green sprout (life/Sei) from dark clouds of germs.

Word Web

Soap Mask Doctor Clean Bacteria Hospital Water Health

Challenge

Try to find 3 products in your house that have the word '衛生' or '衛生的' on them. If you are not in Japan, look up 'Japanese hygiene products' online and identify the kanji.

Word Origin

The word was coined in the late 19th century (Meiji Era) by Nagayo Sensai, a Japanese physician and statesman. He chose it to translate the Western concept of 'hygiene' or 'sanitary science.'

Original meaning: The kanji 衛 (ei) means 'to guard' or 'to defend,' and 生 (sei) means 'life.' Together, they signify 'defending life.'

Sino-Japanese (Kango).

Cultural Context

Be careful when using 'fueisei' (unhygienic) to describe a person's home or habits; it is a very strong and potentially offensive word. It is better to use softer terms in social situations.

In English, 'hygiene' is often personal (showering, teeth). In Japan, 'Eisei' is very often public or industrial (government standards, food safety).

The Food Sanitation Act (食品衛生法) of 1947. The 'Eisei-hei' (Medic) characters in historical anime or manga like 'Golden Kamuy'. Public health posters during the 1918 flu pandemic in Japan.

Practice in Real Life

Real-World Contexts

Cooking/Food Service

食品衛生
衛生管理
消毒
食中毒予防

Medical/Dental

歯科衛生士
口腔衛生
衛生兵
感染防止

School/Education

衛生委員会
保健室
手洗い・うがい
衛生だより

Disaster/Emergency

衛生状態の維持
避難所の衛生
簡易トイレ
防疫

Mental Health

精神衛生
心の健康
ストレス管理
メンタルヘルス

Conversation Starters

"最近、レストランの衛生管理についてどう思いますか？ (What do you think about restaurant hygiene management lately?)"

"精神衛生を保つために、何か特別なことをしていますか？ (Do you do anything special to maintain your mental hygiene?)"

"日本の公衆衛生は世界的に見てどう評価されていると思いますか？ (How do you think Japan's public health is evaluated globally?)"

"子供に衛生習慣を教えるのは難しいと思いますか？ (Do you think it's difficult to teach children hygiene habits?)"

"災害時に一番大切な衛生用品は何だと思いますか？ (What do you think is the most important hygiene product during a disaster?)"

Journal Prompts

今日の自分の精神衛生状態について書いてください。何が影響しましたか？ (Write about your mental hygiene state today. What influenced it?)

あなたが考える『理想的な衛生環境』とはどのようなものですか？ (What is an 'ideal sanitary environment' in your opinion?)

パンデミックを経て、あなたの衛生に対する意識はどう変わりましたか？ (How has your awareness of hygiene changed since the pandemic?)

日本の『清潔さ』と『衛生』の文化について感じたことを書いてください。 (Write about what you felt regarding Japan's culture of 'cleanliness' and 'hygiene'.)

職場や学校での衛生管理を改善するためのアイデアを提案してください。 (Propose ideas for improving hygiene management at your workplace or school.)

Frequently Asked Questions

10 questions

Generally, no. For a messy or dirty room, use 'kitanai' or 'katazuiteinai.' For a clean room, use 'kirei' or 'seiketsu.' Use 'eisei' only if you are talking about health standards, like in a hospital or if there's a mold problem.

No, it is a noun. To use it as a verb, you usually combine it with other words, like '衛生管理をする' (to do hygiene management) or '衛生を保つ' (to maintain hygiene).

It translates to 'mental hygiene.' It refers to keeping your mind healthy and avoiding stress or toxic environments. It's a common way to talk about mental well-being in Japanese.

Use '衛生的' (eiseiteki). Since it is a na-adjective, you say 'eiseiteki na [noun]' (e.g., eiseiteki na mise - a hygienic shop).

It is less common than 'kirei' or 'seiketsu.' It sounds a bit formal or clinical. You'd use it when discussing health rules or if someone is being particularly unsanitary in a way that could cause illness.

It means a combat medic. 'Ei' (guard) + 'Sei' (life) + 'Hei' (soldier). It's the soldier who guards life on the battlefield.

No. Satellite is 衛星 (Ei + Star), while hygiene is 衛生 (Ei + Life). They sound the same, but the second kanji is different.

The most common antonym is 不衛生 (fueisei), meaning unhygienic or unsanitary.

Use 保健 for health-related systems (insurance, school nurse, public health center). Use 衛生 for the actual state of being clean and germ-free.

Yes, 'pet hygiene' is 'petto no eisei.' It's common in contexts like grooming or cleaning up after them.