\ˈkül \

Definition of cool 

(Entry 1 of 4)

1 : moderately cold : lacking in warmth The plant grows best in cool climates.

2a : marked by steady dispassionate calmness and self-control a cool and calculating businessperson

b : lacking ardor or friendliness a cool impersonal manner

c of jazz : marked by restrained emotion and the frequent use of counterpoint (see counterpoint entry 1)

d : free from tensions or violence We used to fight, but we're cool now.

3 used as an intensive a cool million dollars

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

5 : facilitating or suggesting relief from heat a cool dress

6a 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 (see resonance sense 2a)

7 slang

a : very good : excellent That was a really cool movie. also : all right Is getting together Friday night cool with you?

b : fashionable, hip … not happy with the new shoes … because they were not "cool."— Celestine Sibley


cooled; cooling; cools

Definition of cool (Entry 2 of 4)

intransitive verb

1 : to become cool : lose heat or warmth placed the pie in the window to cool sometimes used with off or down

2 : to lose ardor or passion His anger cooled.

transitive verb

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.

2a : 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 itNewsweek

cool it

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

cool one's heels

: to wait or be kept waiting for a long time especially from or as if from disdain or discourtesy



Definition of cool (Entry 3 of 4)

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

2a : 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 The player lost his cool and began yelling at the referee.

3 : hipness



Definition of cool (Entry 4 of 4)

: in a casual and nonchalant manner play it cool

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Other Words from cool


coolish \ ˈkü-​lish \ adjective
coolly or less commonly cooly \ ˈkü(l)-​lē \ adverb
coolness \ ˈkül-​nəs \ noun

Synonyms & Antonyms for cool

Synonyms: Adjective

A-OK, A1, awesome, bang-up, banner, beautiful, blue-chip, blue-ribbon, boffo, bonny (also bonnie) [chiefly British], boss [slang], brag, brave, bully, bumper, capital, choice, classic, corking, crackerjack, cracking, dandy, divine, dope [slang], down [slang], dynamite, excellent, fab, fabulous, famous, fantabulous [slang], fantastic, fine, first-class, first-rate, first-string, five-star, four-star, frontline, gangbusters (also gangbuster), gilt-edged (or gilt-edge), gone [slang], grand, great, groovy, heavenly, high-class, hot, hype [slang], immense, jim-dandy, keen, lovely, marvelous (or marvellous), mean, neat, nifty, noble, number one (also No. 1), numero uno, out-of-sight [slang], par excellence, peachy, peachy keen, phat [slang], prime, primo [slang], prize, prizewinning, quality, radical [slang], righteous [slang], sensational, slick, splendid, stellar, sterling, superb, superior, superlative, supernal, swell, terrific, tip-top, top, top-notch, top-of-the-line, top-shelf, topflight, topping [chiefly British], unsurpassed, wizard [chiefly British], wonderful

Synonyms: Verb

calm (down), chill out [slang], hush, pipe down, quiet, settle (down)

Synonyms: Noun

aplomb, calmness, collectedness, composedness, composure, coolness, countenance, equanimity, equilibrium, imperturbability, placidity, repose, sangfroid, self-composedness, self-possession, serenity, tranquillity (or tranquility), tranquilness

Antonyms: Adjective

atrocious, awful, execrable, lousy, pathetic, poor, rotten, terrible, vile, wretched

Antonyms: Verb

act up, carry on, cut up

Antonyms: Noun

agitation, discomposure, perturbation

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Choose the Right Synonym for 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

Examples of cool in a Sentence


The weather is cool today. The surface is cool to the touch. The plant grows best in cool climates. I'm feeling a little cool. We changed into some cooler clothes. She remained calm, cool, and collected.


The fan cools the engine. the cooling effect of the breeze Allow the cake to cool before slicing. the cooling of the ocean waters I took a break from the discussion to allow my anger to cool. His interest in her has cooled somewhat.


the judge's customary cool stood him in good stead during the sensational trial I envy you your cool.


Here comes Mom. Act cool and she won't suspect a thing.
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Recent Examples on the Web: Verb

That water is mostly for cooling the equipment, but some of it is also used for emissions reduction and other processes essential to operating a power plant. Megan Geuss, Ars Technica, "Thermal power plants use a lot of water, but that’s slowly changing," 13 Nov. 2018 Since 2011, Team USA women’s gymnastics has been on fire—and the powerhouse athletes don't show any signs of cooling down. Jenny Mccoy, SELF, "The USA Women's Gymnastics Team Won Its 4th Straight World Championship—Here's How to Watch the Final Events," 31 Oct. 2018 Once-hot markets are showing signs of cooling down. Christina Rexrode, WSJ, "Mortgage Rates Fast Approaching 5%, a Fresh Blow to Housing Market," 11 Oct. 2018 Because, after all, who doesn't want to hydrate, brighten, and illuminate skin with just a quick hit of mist… and feel a wash of cooling relief all the while? Sarah Kinonen, Allure, "The Best Hydrating Face Mists for Every Skin Type," 15 Aug. 2018 Once cooled scoop your favorite ice cream onto one cookie, then press another cookie on top! Blake Bakkila,, "Avocado Lovers, Rejoice! Whole Foods Is Selling a Dairy-Free Avocado Ice Cream," 28 June 2018 Transfer muffins to a wire rack and eat while warm or let cool completely. Molly Baz, Bon Appetit, "Extra-Corny Cornbread Muffins," 25 June 2018 Let vegetables cool, then transfer to food processor. The Good Housekeeping Test Kitchen, Good Housekeeping, "Great Breakfast Recipes," 21 June 2018 Remove the meat to a cutting board and let cool slightly. Roxanne Wyss And Kathy Moore, kansascity, "Flavorful roast beef highlights this dad’s skill with the grill," 19 June 2018

Recent Examples on the Web: Noun

Last week, Abloh, a bonafide purveyor of cool, celebrated his newest design project amongst some of his closest friends in New York. Chrissy Rutherford, Harper's BAZAAR, "Virgil Abloh Adds Champagne Designer to His Resume," 24 Oct. 2018 The Pastagram would like to be a very specific type of cool, and isn’t, and still tries anyway. Rachel Sugar, Vox, "At the Pastagram, everyone was eating, and no one was taking pictures of it.," 15 Oct. 2018 Even at the tail end of a jet-lag-inducing romp of early morning runways and late night soirees, beauty statements felt intentional—even cinematic—thanks to an uninterrupted backdrop of Parisian cool. Vogue, "The Best Street Style Beauty at Paris Fashion Week," 3 Oct. 2018 Done correctly, a haircut can take fine strands and create an illusion of cool, woke-up-like-this-status volume. Wendy Sy, Allure, "The 8 Best Haircuts to Make Thin Hair Look Way Thicker," 28 Aug. 2018 Choosing patent leather mid-calf moto boots, Kylie looked the picture of casual cool. Avery Matera, Teen Vogue, "Kylie Jenner Wears Gucci, Hermes and Fendi While Out in NYC With Travis Scott," 19 July 2018 After cooking, remove and place in a large container; let cool, then refrigerate. Caron Golden,, "Yogurt: Purely homemade," 25 June 2018 The only one perhaps losing his cool was Jordan, who picked up the first technical foul of his Butler tenure with 6:02 left. David Woods, Indianapolis Star, "Who owns Chicago? Bears or Cubs? Neither: It's Dawgs," 20 Jan. 2018 Consumer reporter Steve Noviello has tips on how to keep cool without wasting energy and money. Leah Napoliello, Houston Chronicle, "BBB on Homes: Set your sights on summertime energy savings," 8 July 2018

Recent Examples on the Web: Adverb

Let cool slightly before serving, or cool completely before storing. Charlotte Druckman, sacbee, "In a churn of events, salted butter is back | The Sacramento Bee," 8 May 2018 Let cool a few minutes, then take egg cups out of muffin pan to cool on a rack. Anna Thomas Bates, Milwaukee Journal Sentinel, "Egg cups make an easy grab-and-go lunch," 21 Feb. 2018 Drain well and let cool before peeling and cutting the eggs in half lengthwise, reserving the yolks. Alysha Witwicki, Milwaukee Journal Sentinel, "What to bring? These side dishes are always welcome at a summer picnic," 29 June 2018 Transfer to a wire rack and let cool before slicing. Steven Satterfield, Country Living, "Buttermilk Cornbread," 1 Feb. 2011 Let cool slightly, then transfer oil and spice mixture to a bowl. Jonah Miller, WSJ, "Throw a Summer Party the Effortless Spanish Way," 6 July 2018 Let cool completely, cover with plastic or store airtight, and store at room temperature. Claire Saffitz, Bon Appetit, "The 10 Baking Questions People Ask Me Literally All the Time, Answered," 21 May 2018 Let cool completely before storing in the refrigerator for up to 3 weeks. Chris Ross,, "New book is collection of low-alcohol drinks," 4 June 2018 New grass needs to be well established before temperatures start to turn cool in late September. Neil Sperry, star-telegram, "Here’s your gardening to-do list for the second part of the summer," 11 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cool.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of cool


before the 12th century, in the meaning defined at sense 1


before the 12th century, in the meaning defined at intransitive sense 1


15th century, in the meaning defined at sense 1


1968, in the meaning defined above

History and Etymology for cool


Middle English col, going back to Old English cōl, going back to West Germanic *kōlu- (whence also Middle Dutch coele "moderately cold" and, from a variant *kōlja-, Old High German kuoli), lengthened-grade derivative from the base of *kalan- "to be cold" — more at cold entry 1


Middle English colen, going back to Old English cōlian, verbal derivative from Germanic *kōl- cool entry 1 (whence also Old Saxon colon "to become cool," Old High German kuolēn)


Middle English cole, derivative of col cool entry 1


derivative of cool entry 1

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Learn More about cool

Dictionary Entries near cool

cook up


cook wrasse





Statistics for cool

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Time Traveler for cool

The first known use of cool was before the 12th century

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More Definitions for cool



English Language Learners Definition of cool

 (Entry 1 of 3)

: 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



English Language Learners Definition of cool (Entry 2 of 3)

: to make (someone or something) cool

: to become cool : to lose heat or warmth

: to become less strong or intense especially in emotion



English Language Learners Definition of cool (Entry 3 of 3)

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


\ˈkül \
cooler; coolest

Kids Definition of cool

 (Entry 1 of 3)

1 : somewhat cold : not warm a cool day a cool room

2 : not letting or keeping in heat cool clothes

3 : calm entry 3 sense 2 She is cool in a crisis.

4 : not interested or friendly: He was cool to my idea.

5 : fashionable, stylish, or attractive in a way that is widely approved of

6 : very good excellent

Other Words from cool

coolly adverb
coolness noun


cooled; cooling

Kids Definition of cool (Entry 2 of 3)

: to make or become less warm



Kids Definition of cool (Entry 3 of 3)

1 : a time or place that is not warm the cool of the evening

2 : a calm state of mind Keep your cool.

Legal Definition of cool 

: to lose passion : become calm sometimes used with off or down the time elapsing…is such that a reasonable man thus provoked would have cooled— W. R. LaFave and A. W. Scott, Jr.

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