Use 'herasu' when you actively make something less in amount or degree.
Word in 30 Seconds
- To make something smaller in quantity or number.
- Used when someone intentionally reduces an amount.
- The intransitive counterpart is 'heru'.
概要
「減らす」は、対象となる物の量や数、あるいは抽象的な概念（時間やリスクなど）を、元の状態よりも少なくする動作を表します。意志を持って行う動作に焦点を当てた他動詞です。2) 使用パターン: 基本的な形は「Aを減らす」です。何が減るのかを示す助詞「を」が必ず伴います。また、どの程度減らすかを示す「～に減らす」「～分減らす」といった表現もよく使われます。3) 一般的な文脈: 日常生活では、食事の量を減らす、支出を減らす、ゴミを減らすといった健康や節約に関連する文脈で頻繁に使用されます。ビジネスシーンでは、コストを削減する（減らす）、作業時間を短縮する（減らす）など、効率化を目的とした表現として重宝されます。4) 類語との比較: 「減る」は自動詞であり、自然に減少する場合に使われます。対して「減らす」は、誰かが意図的に操作して減らすという能動的なニュアンスが強調されます。また、「削る（けずる）」は、不要な部分を取り除いて減らすという、より物理的または比喩的な「カット」のイメージが強い言葉です。
Examples
健康のために塩分を減らしています。
everydayI am reducing salt intake for my health.
経費を減らすための会議を行いました。
formalWe held a meeting to reduce expenses.
もっと宿題を減らしてよ！
informalPlease give us less homework!
二酸化炭素排出量を減らすことが急務である。
academicReducing carbon dioxide emissions is an urgent task.
Common Collocations
Common Phrases
ゴミを減らす
reduce waste
スピードを減らす
slow down / reduce speed
負担を減らす
reduce the burden
Often Confused With
Heru is intransitive and describes a state where something decreases naturally. Herasu is transitive and describes an action taken by someone to cause a decrease.
Kezuru implies removing a portion of something, often by scraping or cutting. Herasu focuses purely on the reduction of the total volume or number.
Grammar Patterns
How to Use It
Usage Notes
Herasu is a standard transitive verb used in both casual and formal settings. When used in very formal business contexts, synonyms like 'sakugen suru' may be preferred. Ensure you always use the particle 'o' to indicate the object being reduced.
Common Mistakes
The most common error is using 'herasu' instead of 'heru' for natural phenomena, such as 'jinkou ga herasu' (incorrect) instead of 'jinkou ga heru' (correct). Always check if the subject is the one doing the action or if the subject is the thing that is naturally decreasing.
Tips
Focus on the transitive nature
Remember that 'herasu' always requires an object marked with 'o'. Think of it as 'I am doing the action of decreasing'.
Don't confuse with intransitive 'heru'
If you say 'kazu ga herasu', it is grammatically incorrect. Use 'kazu ga heru' for natural decrease and 'kazu o herasu' for intentional reduction.
Environmental awareness in Japan
The phrase 'gomi o herasu' (reducing trash) is a core part of Japanese environmental education. It is frequently seen on public posters and government campaigns.
Word Origin
The word originates from the classical Japanese verb 'heru', which meant to diminish or wear away. The suffix '-asu' was added to create the transitive form, indicating the act of causing that diminution.
Cultural Context
In Japanese culture, 'mottainai' (wastefulness) is a key concept. Therefore, 'herasu' is often associated with positive actions like saving food or energy to avoid wasting resources.
Memory Tip
Think of 'Herasu' as 'He-rasu' (He-less). You are making the pile 'less' by taking things away.
Frequently Asked Questions
4 questions「減らす」は他動詞で、人間が意図的に量を減らす動作を指します。一方、「減る」は自動詞で、自然に量が少なくなる状態を表します。
反対語は「増やす（ふやす）」です。数を多くする場合や、量を増大させる場合に使います。
はい、言えます。ただし、ビジネスの文脈では「コストを削減する」という言葉の方がより一般的でプロフェッショナルな響きがあります。
はい、使えます。時間、リスク、ストレスなど、形のない抽象的なものに対しても、その程度や量を減らすという意味で広く使われます。
Test Yourself
健康のために、毎日食べる砂糖の量を___。
目的語「砂糖の量を」があるため、他動詞の「減らします」が適切です。
次のうち、文法的に正しいものはどれですか？
「支出を」という目的語に対して、他動詞「減らした」が正しく使われています。
（塩分を / 減らして / ください / 料理の）
「料理の塩分」を目的語として「減らす」という構成が最も自然です。
Score: /3
Summary
Use 'herasu' when you actively make something less in amount or degree.
- To make something smaller in quantity or number.
- Used when someone intentionally reduces an amount.
- The intransitive counterpart is 'heru'.
Focus on the transitive nature
Remember that 'herasu' always requires an object marked with 'o'. Think of it as 'I am doing the action of decreasing'.
Don't confuse with intransitive 'heru'
If you say 'kazu ga herasu', it is grammatically incorrect. Use 'kazu ga heru' for natural decrease and 'kazu o herasu' for intentional reduction.
Environmental awareness in Japan
The phrase 'gomi o herasu' (reducing trash) is a core part of Japanese environmental education. It is frequently seen on public posters and government campaigns.
Examples
4 of 4健康のために塩分を減らしています。
I am reducing salt intake for my health.
経費を減らすための会議を行いました。
We held a meeting to reduce expenses.
もっと宿題を減らしてよ！
Please give us less homework!
二酸化炭素排出量を減らすことが急務である。
Reducing carbon dioxide emissions is an urgent task.
Related Content
This Word in Other Languages
Related Phrases
Related Vocabulary
More general words
いくつか
B1An unspecified small number of things; some, a few.
ちょっと
A2A little; a moment; a bit. Small amount or short time.
すこし
A2A little; a few.
さっき
A2A little while ago; a short time past.
能力
A1Nouryoku refers to the mental or physical power, skill, or capacity required to perform a specific task or function. It can describe both innate talent and skills acquired through learning and practice.
異常
A1A word used to describe something that deviates from the normal state, standard, or expected pattern. It often implies a problem, malfunction, or an extraordinary occurrence that requires attention or investigation.
～について
A2About, concerning; indicates topic.
〜について
B1About, concerning; on the subject of.
～ぐらい
A2about, approximately
ぐらい
A2About; approximately; to the extent of.
