cool

SayKOOLUS/kul/UK/kuːl/

Adjectivecooler, coolest

Verbcools, cooling, cooled

18 meanings of cool

Practice

1
low temperatureadjective
Somewhat cold rather than warm, or giving a pleasant feeling of relief from heat.
The mountain stream stayed cool even in midsummer.
A cool breeze drifted in through the open window.
Similarfresh, refreshing, crisp
Oppositewarm, hot
Note
The temperature sense the rest of the word grows from: Old English cōl, which could already mean "calm" as well as "cold," from an Indo-European root for cold. That early double meaning is why the "calm" meaning feels so natural. Cool sits between warm and chilly rather than at either end, and it compares freely: astronomers describe dwarf stars as "much cooler" than the sun.
Checked 30 Oct 2026 · 3 facts
Cool derives from Old English cōl, which had both temperature and calmness senses. en.wiktionary.org
The word ultimately derives from an Indo-European root referring to cold. en.wiktionary.org
Astronomers describe dwarf stars as much cooler than the Sun. hq.eso.org
2
impressiveadjectivecolloquial
Very interesting, impressive, or exciting.
We saw a cool magic trick that left everyone amazed.
The documentary showed some cool footage of deep-sea creatures.
Similarawesome, neat
Oppositeboring, dull, lame
3
make colderverbtransitive
To make something cooler, or to lose heat and become cooler.
Engineers cool the reactor with circulating water.
A light wind cooled the runners as they climbed the hill.
UsageOften with down: cool the room down. The means usually follows with: cool it with water.
Similarchill
Oppositeheat, warm
Note
The King James Bible of 1611 asks that Lazarus dip his finger in water and "cool my tongue." The construction has hardly changed since.
Checked 1 Nov 2026 · 2 facts
The King James Bible was first published in 1611. en.wikipedia.org
The King James Bible contains the request that Lazarus dip his finger in water and “cool my tongue”; the speaker is the rich man addressing Abraham in Luke 16:24. en.wikisource.org
4
all rightadjectivecolloquial
Acceptable or all right; also, of a person, willing to accept something ('cool with').
Her parents were cool with her staying out late as long as she texted them.
He said it was cool to swing by his place anytime.
UsageCommon in questions: Is it cool if I...? A person is cool with something they accept.
Similarfine, okay
Oppositeunacceptable
5
stylishadjectivecolloquial
Fashionable and stylish, or admired and popular because of an easy, confident style.
The cafe has a cool, retro look that draws weekend crowds.
Wide-leg jeans are cool again after years out of fashion.
Similarfashionable, stylish, trendy, hip
Oppositeunfashionable, dated, uncool
6
adjective
Calm and in control of oneself, even in difficult or dangerous situations.
The pilot remained cool as the storm buffeted the plane.
Even under fierce questioning, the witness stayed cool.
UsageOften after stay, keep or remain: stay cool under pressure, keep a cool head.
Similarcalm, composed, collected, unflappable, unruffled
Oppositenervous, agitated, flustered, panicky
7
less intenseverbfigurativelyintransitive
Of feelings, interest, or relations, to become or make less warm or intense.
Relations between the two countries cooled after the border dispute.
Tempers cool once people walk away and take a breath.
Similarchill, subside, wane, fade, diminish
Oppositewarm, intensify
8
steady nervesnoununcountable
A calm and composed temperament.
Her cool never wavered through the long negotiation.
When the crowd began heckling, the speaker kept his cool and finished his talk.
UsageMostly in keep your cool and lose your cool, with a possessive word before it.
Similarcomposure, calmness
Oppositepanic, agitation, nervousness

Less common meanings

9
on good termsadjectivecolloquial
Of two people, on good and friendly terms with each other.
Jen and I had a big fight last month, but we talked it out and we're cool now.
We're cool now, no hard feelings about the argument.
UsageAfter a disagreement, we're cool reassures someone that things are fine again. Are we cool? asks for confirmation.
Similarfine, okay, friendly
Oppositeestranged
10
adjective
Showing little enthusiasm; unenthusiastic or doubtful about something.
Voters remained cool to the candidate's untested promises.
She gave the idea a cool reception, unconvinced it would work.
UsageOften cool to or toward an idea, and in a cool reception or a cool response.
Similarlukewarm, tepid, chilly
Oppositewarm
11
blue-greenadjective
Of a color, falling in the range from violet through blue to green.
She repainted the studio in cool grays and soft teals.
The photograph had a cool cast that suited the wintry mood.
Similarcold
Oppositewarm
Note
In talk about color, cool always travels with its partner warm. Cool covers the violets, blues and greens, and warm covers the hues on the other side. The pairing is as often practical advice as description. Someone with a reddish complexion, for instance, may be advised to wear mainly cool colors.
Checked 30 Oct 2026 · 3 facts
Warm and cool are paired color categories, conventionally covering red, orange and yellow versus violet, blue and green. courses.washington.edu
The warm/cool distinction is used in practical advice about selecting clothing colors. pubs.nmsu.edu
Cool colors can make adjacent warm colors appear warmer. Clothing advice should distinguish skin undertones; the university guidance recommends similar cool undertones for pinkish complexions. pubs.nmsu.edu
12
aura of stylenoununcountable
The quality of being popular, stylish, or in fashion.
The actor radiated an effortless cool throughout the interview.
Decades later, the band's cool still defines the whole era.
UsageUsually without a, but a is common with an adjective: an effortless cool, a quiet cool.
Similarstyle, hipness, chic, flair, glamour
13
noununcountable
A moderate, refreshing coldness; air temperature between hot and cold.
They rested in the cool of the evening after a long day's work.
Stepping indoors, she welcomed the cool after the blazing street.
UsageUsually the cool of the evening or morning, or simply the cool.
Similarfreshness
Oppositeheat, warmth
14
big sumadjective
Used before a stated sum of money to emphasize, often jokingly, how large the amount is.
She walked away from the table with a cool five thousand in winnings.
The painting sold for a cool two hundred million at auction.
UsagePut a cool before the amount: a cool million, a cool five thousand.
Similarwhopping
Note
An ironic intensifier that has kept the same frame for centuries: a cool followed by an exact figure. In Henry Fielding's Tom Jones (1749), the gambler Watson needs someone to lend him "a cool hundred", and in Dickens's Great Expectations Joe reports that Miss Havisham left Matthew Pocket "a cool four thousand". Meet Me in St. Louis (1944) prices a World's Fair at "a cool fifty million."
Checked 3 Nov 2026 · 7 facts
The monetary construction 'a cool' followed by a figure has existed for centuries. gutenberg.org
Henry Fielding wrote Tom Jones, first published in 1749. en.wikipedia.org
The gambler Watson says he needs someone to lend him 'a cool hundred'. gutenberg.org
Charles Dickens wrote Great Expectations. gutenberg.org
Joe reports that Miss Havisham left Matthew Pocket 'a cool four thousand'. en.wikisource.org
Meet Me in St. Louis was released in 1944. en.wikipedia.org
The film includes an estimated World's Fair cost of 'a cool fifty million'. en.wiktionary.org
15
relaxverbslangintransitive
To relax and spend time casually, especially hanging out with others.
Instead of going out, we spent Saturday night cooling at Jay's place, playing video games and chatting.
On Sunday afternoons we usually just cool at my cousin's place and play cards.
UsageOften used as cooling, also written coolin'. You can add a place: cooling at my cousin's.
Similarchill, relax, lounge, hang, unwind
Note
A slang verb from African-American Vernacular English, heard most often as coolin'. Ice-T's "6 in the Mornin'" (1986) uses it for his homeboys hanging back somewhere far off. In Paul Beatty's Tuff, "What up, kid?" gets the one-word answer "Coolin'." Courttia Newland's The Scholar (1997) carries it into London speech.
16
interjectioncolloquial
Said in response to signal approval or agreement, or to indicate that something is acceptable or welcome.
"The meeting moved to Thursday." "Cool, that works better for me anyway."
"Mind if I bring my roommate along?" "Sure, cool."
Similarokay, great, fine, nice
17
adjective
Behaving toward someone with little warmth or friendliness, keeping them at a reserved, slightly unwelcoming distance.
The two old friends exchanged a cool handshake, neither quite ready to forgive.
She has been noticeably cooler toward me since I got the promotion.
Usagecool toward (or towards) a person shows distance; cool with a plan means you accept it.
Similarcold, chilly, frosty, distant, aloof
Oppositewarm, friendly, cordial
Note
Here temperature turns into manners: a cool handshake, a cool reception, a friend who has grown cooler toward you.
18
verbdated
To kill or murder a person.
Big-mouth got up as fast as he could, and I was thinking how much heart he had. But I ran toward him like my life depended on it; I wanted to cool him.
1967, Piri Thomas, Down These Mean Streets

Practice

Can you tell the meanings of cool apart? Answer 3 quick questions from this page, or write your own sentence and AI will check it.

Origins

Meanings 1–2, 4–6, 8–14, 16–17

From Middle English cool, from Old English cōl ("cool, cold, calm"), going back through Proto-Germanic to the Proto-Indo-European root *gel- ("cold"). It is related to cold and has cognates such as Dutch koel and German kühl.

Checked 1 Nov 2026 · 3 facts

Cool comes from Middle English cool and Old English cōl, meaning “cool, cold, calm,” through Proto-Germanic from Proto-Indo-European *gel-, referring to cold. en.wiktionary.org
Cool is etymologically related to cold. en.wiktionary.org
Dutch koel and German kühl are cognates of cool. en.wiktionary.org

Meanings 3, 7, 15

Old English cōlian, meaning "to cool, grow cold," became Middle English colen, and it traces back to the Proto-Indo-European root *gel- ("to freeze"). Dutch koelen and German kühlen are cognates. Old English cēlan also fed into the word and was later reshaped to look like the adjective cool.

Checked 1 Nov 2026 · 5 facts

Old English cōlian meant “to cool, grow cold.” en.wiktionary.org
Old English cōlian developed into Middle English colen and modern English cool. en.wiktionary.org
The word ultimately derives from Proto-Indo-European *gel-, meaning “to freeze.” en.wiktionary.org
Dutch koelen and German kühlen are cognates of the English verb cool. en.wiktionary.org
Old English cēlan also contributed to cool, through a form altered to resemble the adjective. en.wiktionary.org