moderately cold; neither warm nor cold: a rather cool evening.
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.
permitting such a sensation: a cool dress.
not excited; calm; composed; under control: to remain cool in the face of disaster.
not hasty; deliberate: a cool and calculated action.
lacking in interest or enthusiasm: a cool reply to an invitation.
lacking in warmth or cordiality: a cool reception.
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
Informal. coolly.
interjection
Slang.
(used to express acceptance): Okay, cool! I'll be there at 10:00.
(used to express approval, admiration, etc.): He got the job? Cool!
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 or off): 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)
to make cool; impart a sensation of coolness to.
to lessen the ardor or intensity of; allay; calm; moderate: Disappointment cooled his early zealousness.
Verb Phrases
cool down, to bring the body back to its normal physiological level after fast, vigorous exercise or activity by gradually slowing the pace of activity or by doing gentle exercises or stretches.
cool off, Informal. to become calmer or more reasonable: Wait until he cools off before you talk to him again.
cool out, Slang. to calm or settle down; relax: cooling out at the beach.
Old English col "not warm" (but usually not as severe as cold), also, of persons, "unperturbed, undemonstrative," from Proto-Germanic *koluz (cf. Middle Dutch coel, Dutch koel, Old High German kuoli, German kühl "cool," Old Norse kala "be cold"), from PIE root *gel- "cold, to freeze" (see cold (adj.)).
Applied since 1728 to large sums of money to give emphasis to amount. Meaning "calmly audacious" is from 1825. Slang use for "fashionable" is 1933, originally Black English; modern use as a general term of approval is from late 1940s, probably from bop talk and originally in reference to a style of jazz; said to have been popularized in jazz circles by tenor saxophonist Lester Young. Related: Coolly.
n.
c.1400, "coldness, coolness," from cool (adj.). Meaning "one's self-control, composure" (the thing you either keep or lose) is from 1966.
v.
Old English colian, "to lose warmth," also figuratively, "to lose ardor," from the root of cool (adj.). Meaning "to cause to lose warmth" is from late 14c. Related: Cooled; cooling.
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