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cool

adj. · v. · n.
US //ˈkuɫ// UK //kˈuːl// cool
  1. 1 temperature (adj.)
    A1 Beginner

    slightly cold in a way that is usually pleasant.

    of a moderately low temperature; refreshing rather than uncomfortably cold.

    Example

    The water in the swimming pool was nice and cool on a hot day.

    Example

    The evening air turned cool as soon as the sun dipped below the horizon, prompting the hikers to reach for their jackets.
  2. 2 fashionable or impressive (adj.)
    A2 Elementary Informal

    fashionable, attractive, or impressive in a modern way.

    denoting something that is fashionable, trendy, or socially impressive. Informal in register.

    Example

    That is a really cool jacket; where did you buy it?

    Example

    The startup's new office has a very cool aesthetic, featuring open spaces and modern art installations.
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  1. 3 calm (adj.)
    B1 Intermediate

    staying calm and not getting angry or upset.

    maintaining composure and emotional control, especially under pressure.

    Example

    He stayed cool during the exam even though the questions were hard.

    Example

    The pilot remained remarkably cool throughout the emergency landing, giving clear instructions to the cabin crew.
  2. 4 acceptable (adj.)
    B1 Intermediate Informal

    used to say that something is okay or that you agree with a plan.

    indicating agreement, approval, or that a situation is acceptable. Primarily informal.

    Example

    If you want to meet at six instead of five, that is cool with me.

    Example

    The manager was cool with the team taking a longer lunch break after they finished the project ahead of schedule.
  3. 5 to lower temperature (v.)
    A2 Elementary

    to become less hot, or to make something less hot.

    to reduce in temperature; to lose or cause to lose heat.

    Example

    Let the soup cool for a few minutes before you eat it.

    Example

    The engineers designed a sophisticated system to cool the server room and prevent the hardware from overheating.
  4. 6 to relax (v.)
    B2 Upper Intermediate Slang Informal

    to spend time relaxing or doing nothing special.

    to spend time relaxing or socialising without a specific purpose. Slang usage.

    Example

    We were just cooling at my house and listening to music.

    Example

    After a stressful week of finals, the students spent the entire Saturday just cooling by the lake.
  5. 7 the cool air (n.)
    B1 Intermediate

    a place or time that is pleasantly cold.

    a state or place of moderate coldness or refreshing temperature.

    Example

    It was a relief to step out of the sun and into the cool of the church.

    Example

    They sat on the porch enjoying the cool of the evening after a particularly humid summer afternoon.
  6. 8 composure (n.)
    B2 Upper Intermediate

    the ability to stay calm and controlled.

    the quality of being calm and in control of one's emotions.

    Example

    The player lost his cool and started shouting at the referee.

    Example

    Maintaining one's cool during a high-stakes negotiation is often the difference between success and failure.
Etymology 1

From Middle English cool, from Old English cōl (“cool, cold, tranquil, calm”), from Proto-West Germanic kōl(ī), from Proto-Germanic kōlaz, kōluz (“cool”), from kalaną (“to be cold, to freeze”), Proto-Indo-European *gel- (“to be cold, to freeze”). Cognates Cognate with North Frisian kuul, kölj (“cold”), Saterland Frisian köil (“cool”), West Frisian koel (“cool”), Cimbrian khuul (“chilly, cool”), Dutch koel (“cool”), German kühl (“cool”), Low German köhl (“cool”), Luxembourgish kill (“cool”), Vilamovian kił (“cool”); also Latin gelū, gelum, gelus (“frost; chill, cold”), Belarusian хо́лад (xólad, “cold”), Bulgarian хлад (hlad, “chill, coolness”), Czech chlad (“cold”), Macedonian лад (lad, “shade; coolness”), Polish chłód (“cold”), Russian and Ukrainian хо́лод (xólod, “cold”), Serbo-Croatian хла̑д, hlȃd (“shade”), Sanskrit जड (jaḍa, “cold; stiff”), जल (jala, “water”). Related to cold.

Etymology 2

From Middle English colen, from Old English cōlian (“to cool, grow cold, be cold”), from Proto-West Germanic kōlēn (“to become cold”), from Proto-Indo-European gel- (“to freeze”). Cognate with Dutch koelen (“to cool”), German kühlen (“to cool”), Swedish kyla (“to cool, refrigerate”). Also partially from Middle English kelen, from Old English cēlan (“to cool, be cold, become cold”), from Proto-West Germanic kōlijan, from Proto-Germanic kōlijaną (“to cool”), altered to resemble the adjective cool. See keel.

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