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B1 verb #3,500 most common 7 min read

扩散

kuosan Top 3,500

Practice it Examples Notes & Tips 扩散 in 30 Seconds

Explanation 扩散 in your Level:

At the A1 level, you don't need to use 扩散 (kuòsàn) often. It's a bit advanced. However, you can think of it as 'moving from one place to many places.' Imagine a smell in a kitchen moving to the living room. That is 扩散. You might see it in very simple science books. It is made of two parts: 'kuò' which means 'big' and 'sàn' which means 'to go away.' So, it means 'becoming big by going away' from the middle. For now, just remember it means 'to spread out.' You can use it for smells or colors in water. It is a verb. For example, 'The smell spreads.'

At the A2 level, you should recognize 扩散 when talking about simple physical things. If you put a drop of ink in a glass of water, the color will 扩散. This word is more formal than just saying 'go everywhere.' It is used for things you can't always catch, like air, smell, or light. You can start to use it with simple directions like '扩散到' (spread to). For example, 'The smoke spread to the bedroom' (烟扩散到了卧室). It is a good word to know if you are interested in science or if you read news about the weather, especially about air pollution (smog).

At the B1 level, 扩散 becomes very important, especially for discussing news and health. You will see it used for the spread of diseases, like the flu or a virus. It's also used for the spread of information or influence. You should be able to use it in sentences like '消息扩散得很快' (The news spread very quickly). You should also know the difference between 扩散 (physical/natural spread) and 传播 (transmitting information/culture). At this level, you might also hear it in medical contexts, such as when a doctor talks about a disease spreading in the body. It is a key word for HSK 4 and 5 preparation.

At the B2 level, you should be comfortable using 扩散 in formal writing and discussions. This includes social issues, scientific processes, and international politics. You should know phrases like '不扩散核武器条约' (Nuclear Non-Proliferation Treaty). You should understand its use in environmental science, such as '污染物扩散' (dispersion of pollutants). You can use it metaphorically as well, describing how a certain feeling or atmosphere spreads through a crowd. Your grammar should include using it as a noun (e.g., '防止扩散') and using complex modifiers to describe the speed and scope of the diffusion.

At the C1 level, you should master the nuances of 扩散 compared to 蔓延, 渗透, and 传播. You should be able to discuss the '扩散效应' (diffusion effect) in economics or sociology, where an innovation or economic growth in one area leads to growth in surrounding areas. You will encounter this word in academic papers, high-level business reports, and literature. You should be able to use it to describe the subtle scattering of light in a poem or the complex proliferation of a digital ideology. Your use of the word should reflect an understanding of its precise scientific roots while applying it to abstract social phenomena.

At the C2 level, 扩散 is a tool for precise expression. You use it to describe the entropy of a system, the mathematical modeling of gas dynamics, or the geopolitical implications of technology proliferation. You can distinguish between 'isotropic diffusion' and 'anisotropic diffusion' in a technical sense (using Chinese terms). You use 扩散 in sophisticated metaphors, perhaps comparing the spread of an ancient philosophy to the slow diffusion of heat through stone. You are expected to have a near-native grasp of its collocations and be able to use it in any professional or academic context without hesitation, recognizing its role in the 'Non-Proliferation' global discourse.

Practice it Examples Notes & Tips

扩散 in 30 Seconds

扩散 (kuòsàn) means to spread out or diffuse, often used for gases, liquids, diseases, or information.
It is composed of '扩' (expand) and '散' (scatter), highlighting the outward movement into a larger space.
It is a formal word used in scientific, medical, and news contexts, but also in daily life for smells or rumors.
Grammatically, it functions as both a verb and a noun, frequently appearing in phrases like '防止扩散' (prevent spread).

The Chinese word 扩散 (kuòsàn) is a powerful and versatile verb that primarily describes the process of something spreading out from a central point to a wider area. In a literal sense, it is frequently used in scientific contexts to describe the diffusion of gases, liquids, or heat. For example, if you open a bottle of perfume in a room, the scent will 扩散 throughout the space. However, its usage extends far beyond the laboratory. In modern Mandarin, it is the standard term for the spread of diseases (like a virus or cancer cells), the distribution of information or rumors, and even the proliferation of technology or weapons.

Scientific Context: Used to describe physical phenomena like gas diffusion or light scattering. It implies a natural, often physical movement from high concentration to low concentration.
Medical Context: Crucial in discussing oncology or epidemiology. It describes cancer cells metastasizing or a virus spreading through a community.
Social/Political Context: Often used in 'nuclear proliferation' (核扩散) or the spread of influence and ideas across borders.

When using 扩散, the focus is on the expansion of the 'area' covered rather than just the 'increase' in quantity.

这种病毒的扩散速度非常快，我们需要立即采取行动。 (The spread of this virus is very fast; we need to take action immediately.)

工厂排放的废气向四周扩散。 (The waste gas emitted by the factory is spreading in all directions.)

消息在社交媒体上迅速扩散开来。 (The news spread rapidly across social media.)

由于风力作用，火势向森林深处扩散。 (Due to the wind, the fire spread deep into the forest.)

我们要防止核武器的扩散。 (We must prevent the proliferation of nuclear weapons.)

Understanding 扩散 requires recognizing that it combines 扩 (to expand/enlarge) and 散 (to scatter/disperse), perfectly capturing the essence of something growing larger by breaking apart and filling space. Whether it's a drop of ink in water or a rumor in a small town, 扩散 is the word that defines that outward journey.

Using 扩散 correctly involves understanding its grammatical role as a verb that can also function as a noun. As a verb, it often takes a directional complement like 出来 (chūlái) or 到 (dào). For instance, '扩散到全国' means 'spread to the whole country.' It is frequently preceded by adverbs of speed, such as 迅速 (xùnsù - rapidly) or 缓慢 (huǎnmàn - slowly).

Subject + 扩散: The most basic form. '烟雾扩散' (Smoke spreads).
Subject + 扩散到 + Place: Indicating the target area. '影响扩散到全球' (The influence spread to the whole world).
Noun Form: Used as the object of '防止' (prevent) or '控制' (control). '控制疾病的扩散' (Control the spread of the disease).

In formal reports, you will see it paired with terms like 范围 (fànwéi - scope) or 速度 (sùdù - speed).

香气的扩散让整个房间都变得很好闻。 (The diffusion of the fragrance made the whole room smell great.)

科学家们正在研究这种气体如何在大气中扩散。 (Scientists are studying how this gas diffuses in the atmosphere.)

这种文化现象正在年轻人中迅速扩散。 (This cultural phenomenon is spreading rapidly among young people.)

医生说癌细胞已经扩散到了肺部。 (The doctor said the cancer cells have already spread to the lungs.)

如果不采取措施，污染会进一步扩散。 (If measures are not taken, the pollution will spread further.)

It is also important to note that 扩散 is generally neutral but often used for negative things (diseases, pollution, rumors). However, it can be positive, like the diffusion of knowledge or beneficial technology. When describing the spread of news, 扩散 implies a ripple effect, where one person tells two, and they tell four, until the whole network is covered.

You will encounter 扩散 in several distinct environments in China. Firstly, in the news. Whenever there is a public health crisis or an environmental issue, the term '扩散' is unavoidable. News anchors will report on the '扩散途径' (pathways of spread) or '扩散趋势' (trends of spread). Secondly, in academic and educational settings. From middle school physics to university-level chemistry and biology, 扩散 is the standard term for diffusion. Students learn about the '扩散作用' (diffusion effect) in cell membranes. Thirdly, in political and international relations discourse. The '不扩散核武器条约' (Non-Proliferation Treaty or NPT) is a major topic in Chinese media when discussing global security.

News Reports: Discussing the spread of COVID-19 or seasonal flu. '加强防控，防止疫情扩散' (Strengthen prevention and control to prevent the epidemic from spreading).
Hospital Settings: Doctors explaining a diagnosis to patients or families. '癌细胞目前还没有扩散' (The cancer cells have not spread yet).
Weather Forecasts: Discussing air quality. '不利于污染物扩散的气象条件' (Weather conditions unfavorable for the dispersion of pollutants).

In everyday life, you might hear a friend say, '别让这个秘密扩散出去' (Don't let this secret spread out). This uses the word in a more colloquial, albeit slightly dramatic, way.

今天的空气质量很差，因为雾霾无法扩散。 (The air quality today is poor because the smog cannot disperse.)

互联网加速了信息的扩散。 (The internet has accelerated the spread of information.)

这种新型技术正从城市向农村扩散。 (This new technology is spreading from cities to rural areas.)

我们要警惕谣言在社区内的扩散。 (We must be wary of the spread of rumors within the community.)

森林大火的扩散范围已经超过了五公顷。 (The spread of the forest fire has exceeded five hectares.)

In summary, 扩散 is a high-frequency word in professional, academic, and journalistic Chinese, but it is also essential for describing physical changes in your environment and the flow of information in social circles.

One of the most common mistakes learners make is confusing 扩散 (kuòsàn) with 传播 (chuánbō). While both can mean 'to spread,' 传播 is usually used for information, culture, or diseases where there is a medium of transmission (like a carrier or a broadcast). 扩散, on the other hand, emphasizes the physical expansion into a larger space. You '传播' a message to an audience, but a gas '扩散' into a room.

Confusion with 扩大 (kuòdà): 扩大 means to enlarge or expand a scale (like expanding a business or a hole), whereas 扩散 means to scatter outward. You can '扩大规模' (expand scale) but you '扩散影响' (spread influence).
Confusion with 蔓延 (mànyán): 蔓延 often implies a slow, creeping, and uncontrollable spread, like fire or weeds. 扩散 is more neutral and can be used for very fast physical processes.

Another mistake is using 扩散 for things that are strictly increasing in number but not area. For example, if your bank balance grows, you don't use 扩散.

Wrong: 他的名声在全世界扩大了。 (His fame enlarged worldwide - sounds awkward). Correct: 他的名声在全世界扩散/传播开了。

Wrong: 这种气味在空气中传播。 (Smell 'broadcasts' in the air - slightly off). Correct: 这种气味在空气中扩散。

Wrong: 这种病在村子里扩大。 (The disease 'enlarged' in the village). Correct: 这种病在村子里扩散。

Wrong: 墨水在纸上传播。 (Ink broadcasts on paper). Correct: 墨水在纸上扩散。

Wrong: 我们要扩散我们的生意。 (We want to diffuse our business). Correct: 我们要扩大我们的生意规模。

Finally, remember that 扩散 is usually an intransitive verb or followed by a prepositional phrase (like '到' or '向'). You don't usually '扩散' something directly as a direct object unless it's in a specific technical context like '扩散知识' (diffusing knowledge), but even then, '传播知识' is more common. Most often, the thing that is spreading is the subject of the sentence.

To master 扩散, you must understand how it relates to its synonyms. The Chinese language has many words for 'spreading,' each with a specific nuance.

传播 (chuánbō): Best for: Information, culture, ideas, viruses. Nuance: Implies a medium or a source 'sending' it out.
蔓延 (mànyán): Best for: Fire, war, diseases, negative influences. Nuance: Implies a creeping, uncontrollable spread like a vine.
散布 (sànbù): Best for: Rumors, seeds, flyers. Nuance: Implies a deliberate scattering by a human agent.
普及 (pǔjí): Best for: Education, technology, products. Nuance: Means to make something common or popular among the general public.

Choosing the right word depends on whether the spread is physical (扩散), social (传播), creeping (蔓延), or intentional (散布).

消息通过广播向全国传播。 (News was broadcast/spread to the whole country via radio.)

火势顺着风向迅速蔓延。 (The fire spread rapidly following the wind direction.)

他在城市遍地散布传单。 (He scattered/distributed flyers all over the city.)

九年义务教育已经全面普及。 (Nine-year compulsory education has been fully popularized.)

这种新药的影响力正在扩散。 (The influence of this new drug is spreading.)

In academic writing, you might also encounter 渗透 (shèntòu - permeate/osmosis), which is a specific type of diffusion through a barrier. Using these words accurately will significantly elevate your Chinese level, showing that you understand not just the basic meaning of 'spread' but the specific physics and social dynamics behind the movement.

How Formal Is It?

Fun Fact

The character 散 (sàn) originally depicted hemp being beaten to separate the fibers, which is a perfect metaphor for scattering.

Pronunciation Guide

UK /kwɔː sæn/

US /kwɔ sæn/

Both syllables are stressed equally due to the fourth tone in Mandarin.

Rhymes With

落 (luò) 阔 (kuò) 办 (bàn) 慢 (màn) 站 (zhàn) 看 (kàn) 饭 (fàn) 蛋 (dàn)

Common Errors

Pronouncing 'sàn' as 'shàn'.
Using the third tone for 'kuò'.
Confusing 'kuò' with 'kū' (wither).

Difficulty Rating

Reading 3/5

Common in news and science; requires knowledge of two medium-level characters.

Writing 4/5

The character '扩' and '散' have many strokes and require practice.

Speaking 3/5

Clear pronunciation but requires correct fourth tones.

Listening 3/5

Easily recognized in formal contexts like news broadcasts.

What to Learn Next

Prerequisites

扩大散步散开面积方向

Learn Next

蔓延传播不扩散渗透普及

Advanced

弥散衍射辐射拓扑熵

Grammar to Know

Directional Complements

扩散 + 出来/出去

Resultative Complements

扩散 + 开了

Prepositional Phrases with '向'

向四周扩散

Prepositional Phrases with '到'

扩散到全身

Adverbial Modifiers

迅速/缓慢 + 扩散

Examples by Level

花香在扩散。

The flower scent is spreading.

Simple Subject + Verb.

红色的墨水在水里扩散。

Red ink is spreading in the water.

Subject + Prepositional Phrase + Verb.

烟雾扩散开了。

The smoke spread out.

Verb + Resultative Complement (开了).

味道在家里扩散。

The smell is spreading in the house.

Location + Verb.

光在水中扩散。

Light diffuses in water.

Simple scientific observation.

热量会扩散。

Heat will spread.

Subject + Modal Verb + Verb.

气味向四周扩散。

The smell spreads in all directions.

Directional Preposition (向).

不要让火扩散。

Don't let the fire spread.

Imperative with 让.

这种香味很快就扩散到了全屋。

This fragrance quickly spread to the whole house.

Adverb (很快) + Verb + Complement (到).

工厂的烟向城市扩散。

The factory smoke is spreading towards the city.

Directional movement.

这种颜色在纸上慢慢扩散。

This color is slowly spreading on the paper.

Adverb (慢慢) + Verb.

我们要防止病毒扩散。

We must prevent the virus from spreading.

Verb as an object of '防止'.

消息在朋友圈里扩散。

The news is spreading in the Moments (social media).

Abstract usage.

空气中的灰尘正在扩散。

The dust in the air is spreading.

Progressive aspect (正在).

那个秘密已经扩散出去了。

That secret has already spread out.

Verb + Directional Complement (出去).

这种植物的种子会随风扩散。

The seeds of this plant spread with the wind.

Natural process description.

随着互联网的发展，信息扩散的速度变快了。

With the development of the internet, the speed of information diffusion has become faster.

Noun phrase as subject.

医生发现，癌细胞已经扩散到了其他器官。

The doctor found that the cancer cells had already spread to other organs.

Medical context.

由于没有风，雾霾很难扩散。

Because there is no wind, it is hard for the smog to disperse.

Causal relationship.

这种新型文化正在年轻人中迅速扩散。

This new type of culture is spreading rapidly among young people.

Social context.

我们需要采取措施来控制疫情的扩散。

We need to take measures to control the spread of the epidemic.

Purpose clause.

这种气体的扩散过程非常有趣。

The diffusion process of this gas is very interesting.

Scientific description.

谣言的扩散给他的生活带来了麻烦。

The spread of rumors brought trouble to his life.

Noun usage.

这种技术已经扩散到了很多发展中国家。

This technology has already spread to many developing countries.

Technological proliferation.

各国都在努力执行《不扩散核武器条约》。

All countries are working hard to implement the Treaty on the Non-Proliferation of Nuclear Weapons.

Fixed political term.

污染物在河流中的扩散受到水流速度的影响。

The dispersion of pollutants in the river is affected by the speed of the water flow.

Passive voice structure.

这种思想的扩散对当时的社会产生了深远影响。

The spread of this idea had a profound impact on the society of that time.

Historical/Abstract context.

由于缺乏有效的通风系统，有害气体在室内迅速扩散。

Due to the lack of an effective ventilation system, harmful gases spread rapidly indoors.

Complex causal structure.

我们要防止这种负面情绪在团队中扩散。

We must prevent this negative emotion from spreading within the team.

Psychological usage.

这种商业模式正在全球范围内快速扩散。

This business model is rapidly spreading on a global scale.

Economic context.

光线通过磨砂玻璃时会发生扩散。

Light diffuses when it passes through frosted glass.

Physics context.

这种病毒的扩散路径依然不明确。

The transmission path of this virus is still unclear.

Formal investigation.

城市化的扩散导致了周边生态环境的巨大变化。

The spread of urbanization has led to massive changes in the surrounding ecological environment.

Sociological context.

在真空中，气体的扩散遵循特定的物理定律。

In a vacuum, the diffusion of gas follows specific physical laws.

Academic physics.

这种艺术风格的扩散标志着一个新时代的到来。

The spread of this artistic style marks the arrival of a new era.

Art history context.

政府采取了紧急干预措施，以遏制金融危机的扩散。

The government took emergency intervention measures to curb the spread of the financial crisis.

Economic crisis management.

通过扩散效应，中心城市的繁荣带动了周边城镇的发展。

Through the diffusion effect, the prosperity of central cities has driven the development of surrounding towns.

Regional economics.

这种微观粒子的扩散速度取决于温度和压力。

The diffusion rate of these microscopic particles depends on temperature and pressure.

Scientific precision.

社交媒体算法在某种程度上加速了极端主义倾向的扩散。

To some extent, social media algorithms have accelerated the spread of extremist tendencies.

Critical social analysis.

该地区的冲突有向邻国扩散的风险。

The conflict in the region risks spreading to neighboring countries.

Geopolitical risk assessment.

各向异性扩散在图像处理中被广泛用于边缘保留平滑。

Anisotropic diffusion is widely used in image processing for edge-preserving smoothing.

Technical computer science.

我们需要从多维度分析该文化基因在不同族群间的扩散机制。

We need to analyze the diffusion mechanism of this cultural gene (meme) among different ethnic groups from multiple dimensions.

High-level academic discourse.

核不扩散体系的脆弱性引发了国际社会的广泛担忧。

The fragility of the nuclear non-proliferation regime has sparked widespread concern in the international community.

Advanced political science.

熵增原理在某种意义上可以看作是能量扩散的终极体现。

The principle of increasing entropy can, in a sense, be seen as the ultimate manifestation of energy diffusion.

Philosophical physics.

该学说的扩散并非一蹴而就，而是经历了长期的博弈与融合。

The spread of this theory was not achieved overnight but underwent a long process of gaming and integration.

Sophisticated historical analysis.

在非线性动力学系统中，扰动的扩散往往呈现出不可预测的特征。

In non-linear dynamic systems, the diffusion of disturbances often exhibits unpredictable characteristics.

Advanced mathematics/physics.

这种创新扩散模型揭示了早期采用者在市场推广中的核心作用。

This innovation diffusion model reveals the core role of early adopters in market promotion.

Marketing theory.

法律观念的扩散是社会现代化进程中的重要组成部分。

The diffusion of legal concepts is an important component of the process of social modernization.

Legal sociology.

Synonyms

传播蔓延普及散布流传

Antonyms

聚集收缩集中

Common Collocations

扩散速度

防止扩散

癌细胞扩散

气体扩散

信息扩散

扩散范围

核扩散

向外扩散

无法扩散

迅速扩散

Common Phrases

扩散作用

— The process of diffusion in science.

这是扩散作用的结果。

扩散系数

— Diffusion coefficient in physics.

计算该物质的扩散系数。

疫情扩散

— The spread of an epidemic.

严防疫情扩散。

不扩散

— Non-proliferation.

签署不扩散条约。

热扩散

— Thermal diffusion.

研究金属的热扩散。

光扩散

— Light diffusion.

使用光扩散板。

文化扩散

— Cultural diffusion.

文化扩散改变了当地习惯。

技术扩散

— Technology diffusion/transfer.

促进先进技术的扩散。

城市扩散

— Urban sprawl/expansion.

城市扩散占用了农田。

扩散源

— Source of diffusion.

寻找污染的扩散源。

Often Confused With

扩散 vs 扩大

扩大 is to make the size or scale bigger (like a room), 扩散 is to spread out (like a smell).

扩散 vs 扩张

扩张 often refers to aggressive expansion of power, territory, or blood vessels.

扩散 vs 传播

传播 is for information/media/viruses with a carrier; 扩散 is physical diffusion.

Idioms & Expressions

"无孔不入"

— Entering every hole; spreading everywhere like air or water.

谣言像空气一样无孔不入。

Colloquial

"星火燎原"

— A single spark can start a prairie fire; small things spreading fast.

这种思想具有星火燎原之势。

Literary

"家喻户晓"

— Known to every household; information has spread completely.

这个故事已经家喻户晓。

Common

"风起云涌"

— Like rising wind and surging clouds; spreading fast and powerfully.

革命运动风起云涌。

Literary

"如火如荼"

— Like a spreading fire; intense and widespread.

建设工作进行得如火如荼。

Literary

"蔓延开来"

— Creeping and spreading out.

恐惧在人群中蔓延开来。

Common

"不胫而走"

— Spread without legs; news spreading rapidly.

消息不胫而走。

Idiomatic

"遍地开花"

— Blossoming everywhere; spreading to all locations.

我们的业务已经遍地开花。

Metaphorical

"声势浩大"

— Great momentum; spreading with a loud voice and large scale.

游行队伍声势浩大。

Formal

"推而广之"

— To extend or spread a principle to other things.

这个道理可以推而广之。

Formal

Easily Confused

扩散 vs 蔓延

Both mean spread.

蔓延 is slow and creeping like a plant; 扩散 is general diffusion.

火势蔓延 (Fire creeps), 气体扩散 (Gas diffuses).

扩散 vs 散布

Both involve scattering.

散布 is usually intentional by humans (rumors/seeds).

散布谣言 (Spread rumors deliberately).

扩散 vs 渗透

Both are scientific.

渗透 involves passing through a barrier or membrane.

水渗透墙壁 (Water permeates the wall).

扩散 vs 普及

Both involve reaching more people.

普及 means to make common or popular.

普及教育 (Popularize education).

扩散 vs 流传

Both involve moving through a population.

流传 is for stories or legends over time.

故事流传至今 (The story has been passed down until now).

Sentence Patterns

S + 扩散 + 了

味道扩散了。

S + 扩散到 + Place

消息扩散到全校。

防止 + N + 扩散

防止疫情扩散。

向 + Direction + 扩散

向四周扩散。

S + 迅速/缓慢 + 扩散

火势迅速扩散。

Noun + 的扩散 + 影响了 + N

污染的扩散影响了居民。

通过 + 扩散作用 + V

通过扩散作用进入细胞。

基于 + 扩散模型 + V

基于扩散模型进行分析。

Word Family

Nouns

扩散器 (diffuser)

扩散性 (diffusibility)

Verbs

扩 (expand)

散 (scatter)

扩大 (enlarge)

Adjectives

扩散的 (diffused)

扩张

散开

传播

蔓延

普及

How to Use It

frequency

High in news, science, and medicine; moderate in daily conversation.

Common Mistakes

Using 扩散 for enlarging a business. → 扩大 (kuòdà)
扩散 involves scattering, whereas 扩大 involves increasing scale.
Using 传播 for gas diffusion. → 扩散 (kuòsàn)
传播 is for information/media; 扩散 is for physical particles.
Pronouncing 'sàn' as 'sān'. → sàn (4th tone)
The fourth tone is required for the word meaning 'scatter'.
Saying '我的病扩散了' for a cold. → 传染 (chuánrǎn)
扩散 is for cancer/serious spread; a cold is 'infecting' others.
Using 扩散 to mean 'popularize' a product. → 普及 (pǔjí)
扩散 is the process of spreading; 普及 is the state of being common.

Tips

Formal Usage

In HSK essays, use 扩散 when discussing environmental or health issues.

Tone Practice

Practice saying 'kuò' and 'sàn' together as they are both sharp falling tones.

Visual Aid

Visualize a ripple in a pond; that outward movement is 扩散.

Word Pairs

Remember the pair '防止扩散' (prevent spread) as it is extremely common.

Complements

Use '到' after 扩散 to specify where the thing has spread to.

Global Issues

Link 扩散 to global topics like 'Nuclear Non-Proliferation' to remember its formal side.

Not for Size

Don't use 扩散 to say you grew taller or a building got bigger.

News Keywords

When you hear '疫情' (epidemic), listen for '扩散' immediately after.

Physics Link

If you know the English word 'diffusion,' 扩散 is its direct equivalent.

Memorize It

Mnemonic

Think of 'Kuo' as 'Quota' expanding, and 'San' as 'Sand' scattering in the wind.

Visual Association

Imagine a drop of ink hitting a bowl of water and slowly turning the whole bowl blue.

Word Web

Ink in water Virus Rumors Nuclear weapons Perfume Smog Heat Light

Challenge

Try to use 扩散 in a sentence about your favorite smell spreading in your house today.

Word Origin

The word is a compound of two characters: 扩 (kuò) and 散 (sàn). 扩 means to expand or open up, while 散 means to scatter or break apart.

Original meaning: To scatter and expand outward.

Sino-Tibetan (Chinese).

Cultural Context

Be careful using 扩散 when talking about serious illnesses like cancer, as it is a sensitive medical term.

In English, 'diffusion' is often technical, while 'spread' is general. 扩散 covers both.

Treaty on the Non-Proliferation of Nuclear Weapons (不扩散核武器条约) Diffusion of Innovations theory by Everett Rogers (创新扩散理论) Cancer metastasis (癌症扩散)

Practice in Real Life

Real-World Contexts

Science Lab

扩散速率
扩散浓度
分子扩散
热扩散

Hospital

癌细胞扩散
病情扩散
感染扩散
扩散范围

News/Politics

不扩散条约
疫情扩散
谣言扩散
影响扩散

Environment

污染物扩散
雾霾扩散
废气扩散
水质扩散

Social Media

信息扩散
视频扩散
秘密扩散
迅速扩散

Conversation Starters

"你觉得互联网是如何加速信息扩散的？"

"如果发现癌细胞扩散了，医生通常会怎么建议？"

"为什么在没有风的日子里，雾霾很难扩散？"

"你认为哪种文化现象在你的国家扩散得最快？"

"我们应该如何防止虚假信息在社交媒体上扩散？"

Journal Prompts

描述一次你看到墨水或颜料在水中扩散的情景。

写一写关于一个秘密是如何在你的朋友圈里扩散开的。

讨论一下你认为科技扩散对发展中国家的利与弊。

如果你能阻止一种东西在世界上扩散，你会选择什么？为什么？

分析一下某种流行时尚是如何在年轻人中扩散的。

Frequently Asked Questions

10 questions

Yes, you can say '消息在社交媒体上扩散' (The news spread on social media), though '传播' is also very common here.

No, it is neutral. You can have the 扩散 of knowledge or pleasant smells, although it is often used for viruses or pollution.

扩大 (kuòdà) means to enlarge a fixed thing, like expanding a business. 扩散 (kuòsàn) means to scatter or move outward, like smoke.

It is '核不扩散' (hé bù kuòsàn).

It is both. As a verb: '病毒在扩散'. As a noun: '防止病毒的扩散'.

Use 扩散 (kuòsàn). It is the standard medical term for metastasis.

Yes, '光扩散' refers to the diffusion of light, often through a filter.

It is '扩散速率' (kuòsàn sùlǜ) or '扩散速度' (kuòsàn sùdù).

Yes, '扩散效应' (diffusion effect) describes how economic growth in one area affects others.

Often, yes. It implies a natural movement from a source to the surroundings.