cool
Americanadjective
-
moderately cold; neither warm nor cold.
a rather cool evening.
- Antonyms:
- warm
-
feeling comfortably or moderately cold.
I'm perfectly cool, but open the window if you feel hot.
-
imparting a sensation of moderate coldness or comfortable freedom from heat.
a cool breeze.
- Antonyms:
- warm
-
permitting such a sensation.
a cool dress.
- Antonyms:
- warm
-
not excited; calm; composed; under control.
to remain cool in the face of disaster.
- Synonyms:
- quiet, placid, unruffled, self-possessed, collected
-
not hasty; deliberate.
a cool and calculated action.
-
lacking in interest or enthusiasm.
a cool reply to an invitation.
- Antonyms:
- warm
-
lacking in warmth or cordiality.
a cool reception.
- Antonyms:
- warm
-
calmly audacious or impudent.
a cool lie.
-
aloof or unresponsive; indifferent.
He was cool to her passionate advances.
-
unaffected by emotions; disinterested; dispassionate.
She made a cool appraisal of all the issues in the dispute.
-
Informal. (of a number or sum) without exaggeration or qualification.
a cool million dollars.
-
(of colors) with green, blue, or violet predominating.
-
Slang.
-
great; fine; excellent.
a real cool comic.
-
characterized by great facility; highly skilled or clever.
cool maneuvers on the parallel bars.
-
socially adept.
It's not cool to arrive at a party too early.
-
acceptable; satisfactory; okay.
If you want to stay late, that's cool.
-
adverb
interjection
noun
-
something that is cool; a cool part, place, time, etc..
in the cool of the evening.
-
coolness.
-
calmness; composure; poise.
an executive noted for maintaining her cool under pressure.
verb (used without object)
-
to become cool (sometimes followed by down oroff ).
The soup cooled in five minutes. We cooled off in the mountain stream.
-
to become less ardent, cordial, etc.; become moderate.
verb (used with object)
verb phrase
-
cool off to become calmer or more reasonable.
Wait until he cools off before you talk to him again.
-
cool down. see cooldown.
-
cool out to calm or settle down; relax.
cooling out at the beach.
adjective
-
moderately cold
a cool day
-
comfortably free of heat
a cool room
-
producing a pleasant feeling of coldness
a cool shirt
-
able to conceal emotion; calm
a cool head
-
lacking in enthusiasm, affection, cordiality, etc
a cool welcome
-
calmly audacious or impudent
-
informal (esp of numbers, sums of money, etc) without exaggeration; actual
a cool ten thousand
-
(of a colour) having violet, blue, or green predominating; cold
-
(of jazz) characteristic of the late 1940s and early 1950s, economical and rhythmically relaxed
-
informal sophisticated or elegant, esp in an unruffled way
-
informal excellent; marvellous
adverb
noun
-
coolness
the cool of the evening
-
slang calmness; composure (esp in the phrases keep or lose one's cool )
-
slang unruffled elegance or sophistication
verb
-
to make or become cooler
-
to lessen the intensity of (anger or excitement) or (of anger or excitement) to become less intense; calm down
-
slang (usually imperative) to calm down; take it easy
-
to wait or be kept waiting
Related Words
Other Word Forms
Etymology
Origin of cool
First recorded before 1000; Middle English col, coul, Old English cōl; cognate with Middle Low German kōl, Old High German kuoli, German kühl; see cold, chill
Explanation
When the weather is cool, it's not quite cold but not warm either. When people are cool, they're mellow and in control. Cool has many meanings. When the weather goes from 70 degrees to 50, it cooled off. A winning pool player who starts losing also cools off. Drinking lemonade on a hot day is yet another way to cool off. When you lose your temper, you lose your cool. Hot cookies should cool before you eat them. Something fashionable is cool, but if you're cool to an idea, you're not so sure about it. Any situation that becomes less intense has cooled.
Vocabulary lists containing cool
Words for Cheese Writers
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Visual Arts - Introductory
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Visual Arts - High School
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
And in the case of the Indy adventure particularly, McLaren F1 boss Zak Brown is a motorsport fan through and through and he thought it was a cool thing to do.
From BBC • May 19, 2026
Households will pay an estimated $778 on average to cool their homes this summer, according to the NEADA.
From MarketWatch • May 18, 2026
These devices trap single ions such as aluminum or ytterbium, cool them to temperatures near absolute zero, and control their quantum states using lasers.
From Science Daily • May 18, 2026
“China would be smart to cool it a little bit. They ought to both cool it.”
From Los Angeles Times • May 17, 2026
She closed her eyes, absorbing the cool air, when she heard the impossible boy calling her name.
From "Legendary Frybread Drive-In" by Cynthia Leitich Smith
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.