# vapor

/ˈveɪpɝ/ (US) · /vˈeɪpɐ/ (UK)

Source: https://englishreference.com/word/vapor
Updated: 2026-06-20

## Senses

### 1. mist or steam

noun · CEFR B2 · American English

a cloud of very small drops of liquid in the air, like steam or mist.

For teachers: a visible suspension of fine particles or droplets in the air, such as mist, steam, or fumes.

- The morning sun caused a thick vapor to rise from the lake.
- As the temperature dropped, a dense vapor began to cling to the valley floor, reducing visibility for the early morning commuters.

Usage: Uncountable when referring to the general substance; countable when referring to specific types or clouds.

### 2. gaseous state

noun · CEFR C1 · American English · Technical

the gas form of something that is usually a liquid or solid.

For teachers: the gaseous phase of a substance that normally exists as a liquid or solid at standard temperature and pressure.

- Water turns into vapor when it reaches its boiling point.
- The laboratory was equipped with specialized ventilation to extract the toxic chemical vapors produced during the experiment.

Usage: Commonly used in chemistry and physics contexts.

### 3. the vapors

noun · CEFR C2 · American English · Archaic

an old-fashioned way to describe feeling nervous, dizzy, or sad.

For teachers: a historical term for a state of depression, hysteria, or nervous faintness.

- In the old novel, the lady suffered from the vapors after hearing the bad news.
- The Victorian protagonist was prone to the vapors, frequently requiring a quiet room and smelling salts to recover her composure.

Usage: Almost always used in the plural form as 'the vapors'.

Teaching tip: This is mostly found in 18th and 19th-century literature; modern speakers only use it humorously.

### 4. to turn into gas

verb · CEFR C1 · American English · Technical

to turn into a gas or to give off steam.

For teachers: to convert into vapor or to emit substances in a gaseous state.

- The liquid began to vapor as it was heated on the stove.
- The volatile compounds will vapor quickly if left uncovered in a warm environment.

Usage: Intransitive in this sense.

## Examples

- Water vapor rises from the pan as the water boils.
- The mechanic warned that the gasoline vapor in the garage could be dangerous if someone lit a match.
- As the temperature dropped rapidly overnight, the water vapor in the atmosphere condensed into a thick fog that blanketed the valley floor until sunrise.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.