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adjective \ˈkül\

Simple Definition of cool

  • : somewhat cold : not warm or hot

  • : made of a light, thin material that helps you stay cool

  • : able to think and act in a calm way : not affected by strong feelings

Full Definition of cool

  1. 1 :  moderately cold :  lacking in warmth

  2. 2 a :  marked by steady dispassionate calmness and self-control <a cool and calculating administrator — Current Biography> b :  lacking ardor or friendliness <a cool impersonal manner> c of jazz :  marked by restrained emotion and the frequent use of counterpoint d :  free from tensions or violence <we used to fight, but we're cool now>

  3. 3 —used as an intensive <a cool million dollars>

  4. 4 :  marked by deliberate effrontery or lack of due respect or discretion <a cool reply>

  5. 5 :  facilitating or suggesting relief from heat <a cool dress>

  6. 6 a of a color :  producing an impression of being cool; specifically :  of a hue in the range violet through blue to green b of a musical tone :  relatively lacking in timbre or resonance

  7. 7 slang a :  very good :  excellent; also :  all right b :  fashionable, hip <not happy with the new shoes … because they were not cool — Celestine Sibley>

cool·ish play \ˈkü-lish\ adjective
cool·ly also cooly play \ˈkü(l)-lē\ adverb
cool·ness play \ˈkül-nəs\ noun

Examples of cool

  1. The weather is cool today.

  2. The surface is cool to the touch.

  3. The plant grows best in cool climates.

  4. I'm feeling a little cool.

  5. We changed into some cooler clothes.

  6. She remained calm, cool, and collected.

Origin of cool

Middle English col, from Old English cōl; akin to Old High German kuoli cool, Old English ceald cold — more at cold

First Known Use: before 12th century

Synonym Discussion of cool

cool, composed, collected, unruffled, imperturbable, nonchalant mean free from agitation or excitement. cool may imply calmness, deliberateness, or dispassionateness <kept a cool head>. composed implies freedom from agitation as a result of self-discipline or a sedate disposition <the composed pianist gave a flawless concert>. collected implies a concentration of mind that eliminates distractions especially in moments of crisis <the nurse stayed calm and collected>. unruffled suggests apparent serenity and poise in the face of setbacks or in the midst of excitement <harried but unruffled>. imperturbable implies coolness or assurance even under severe provocation <the speaker remained imperturbable despite the heckling>. nonchalant stresses an easy coolness of manner or casualness that suggests indifference or unconcern <a nonchalant driver>.




Simple Definition of cool

  • : to make (someone or something) cool

  • : to become cool : to lose heat or warmth

  • : to become less strong or intense especially in emotion

Full Definition of cool

  1. intransitive verb
  2. 1 :  to become cool :  lose heat or warmth <placed the pie in the window to cool> —sometimes used with off or down

  3. 2 :  to lose ardor or passion <his anger cooled>

  4. transitive verb
  5. 1 :  to make cool :  impart a feeling of coolness to <cooled the room with a fan> —often used with off or down <a swim cooled us off a little>

  6. 2 a :  to moderate the heat, excitement, or force of :  calm <cooled her growing anger> b :  to slow or lessen the growth or activity of —usually used with off or down <wants to cool off the economy without freezing it — Newsweek>

cool it
  1. :  to calm down :  go easy <the word went out to the young to cool it — W. M. Young>

cool one's heels
  1. :  to wait or be kept waiting for a long time especially from or as if from disdain or discourtesy

Examples of cool

  1. The fan cools the engine.

  2. the cooling effect of the breeze

  3. Allow the cake to cool before slicing.

  4. the cooling of the ocean waters

  5. I took a break from the discussion to allow my anger to cool.

  6. His interest in her has cooled somewhat.

Before 12th Century

First Known Use of cool

before 12th century




Definition of cool

  1. 1 :  a cool time, place, or situation <the cool of the evening>

  2. 2 a :  absence of excitement or emotional involvement :  detachment <must surrender his fine cool and enter the closed crazy world of suicide — Wilfrid Sheed> b :  poise, composure <press questions … seemed to rattle him and he lost his coolNew Republic>

  3. 3 :  hipness

Examples of cool

  1. <the judge's customary cool stood him in good stead during the sensational trial>

  2. <I envy you your cool.>

15th Century

First Known Use of cool

15th century




Simple Definition of cool

  • : in a calm manner : in a way that does not seem unusual or excited

Full Definition of cool

  1. :  in a casual and nonchalant manner <play it cool>

Examples of cool

  1. Here comes Mom. Act cool and she won't suspect a thing.


First Known Use of cool


Seen and Heard

What made you want to look up cool? Please tell us where you read or heard it (including the quote, if possible).


February 7, 2016

a slight offense

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