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vapor

n. · v.
US //ˈveɪpɝ// UK //vˈeɪpɐ// va·por
  1. 1 mist or steam (n.)
    B2 Upper Intermediate American English

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

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

    Example

    The morning sun caused a thick vapor to rise from the lake.

    Example

    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. 2 gaseous state (n.)
    C1 Advanced American English Technical Science

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

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

    Example

    Water turns into vapor when it reaches its boiling point.

    Example

    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.

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  1. 3 the vapors (n.)
    C2 Proficiency American English Archaic

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

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

    Example

    In the old novel, the lady suffered from the vapors after hearing the bad news.

    Example

    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'.

    Teacher's tip

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

  2. 4 to turn into gas (v.)
    C1 Advanced American English Technical Science

    to turn into a gas or to give off steam.

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

    Example

    The liquid began to vapor as it was heated on the stove.

    Example

    The volatile compounds will vapor quickly if left uncovered in a warm environment.

    Usage

    Intransitive in this sense.

Origin

From Middle English vapour, from Anglo-Norman vapour, Old French vapor, from Latin vapor (“steam, heat”).

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