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
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
7
informal
b
: fashionable, hip
… not happy with the new shoes … because they were not "cool."— Celestine Sibley
cool
verb
cooled; cooling; cools
Definition of cool (Entry 2 of 4)
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.
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 it — Newsweek
cool it
cool one's heels
: to calm down : go easy
The word went out to the young to cool it.— W. M. Young
: to wait or be kept waiting for a long time especially from or as if from disdain or discourtesy
cool
nounDefinition 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
3
: hipness
cool
adverbDefinition of cool (Entry 4 of 4)
: in a casual and nonchalant manner
play it cool
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Merriam-Webster unabridged
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Time Traveler for cool
The first known use of cool was before the 12th century
See more words from the same century