'Cooler' definitions:

Definition of 'cooler'

noun

A refrigerator for cooling liquids [syn: cooler, ice chest]

noun

An iced drink especially white wine and fruit juice

noun

A cell for violent prisoners [syn: cooler, tank]

From: GCIDE

Cool \Cool\, a. [Compar. Cooler; superl. Coolest.] [AS. c[=o]l; akin to D. koel, G. k["u]hl, OHG. chouli, Dan. k["o]lig, Sw. kylig, also to AS. calan to be cold, Icel. kala. See Cold, and cf. Chill.]
1. Moderately cold; between warm and cold; lacking in warmth; producing or promoting coolness. [1913 Webster]
Fanned with cool winds. --Milton. [1913 Webster]
2. Not ardent, warm, fond, or passionate; not hasty; deliberate; exercising self-control; self-possessed; dispassionate; indifferent; as, a cool lover; a cool debater. [1913 Webster]
For a patriot, too cool. --Goldsmith. [1913 Webster]
3. Not retaining heat; light; as, a cool dress. [1913 Webster]
4. Manifesting coldness or dislike; chilling; apathetic; as, a cool manner. [1913 Webster]
5. Quietly impudent; negligent of propriety in matters of minor importance, either ignorantly or willfully; presuming and selfish; audacious; as, cool behavior. [1913 Webster]
Its cool stare of familiarity was intolerable. --Hawthorne. [1913 Webster]
6. Applied facetiously, in a vague sense, to a sum of money, commonly as if to give emphasis to the largeness of the amount. [1913 Webster]
He had lost a cool hundred. --Fielding. [1913 Webster]
Leaving a cool thousand to Mr. Matthew Pocket. --Dickens.
Syn: Calm; dispassionate; self-possessed; composed; repulsive; frigid; alienated; impudent. [1913 Webster]

From: GCIDE

Cooler \Cool"er\, n. That which cools, or abates heat or excitement. [1913 Webster]
If acid things were used only as coolers, they would not be so proper in this case. --Arbuthnot. [1913 Webster]
2. Anything in or by which liquids or other things are cooled, as an ice chest, a vessel for ice water, etc. [1913 Webster]
3. An alcoholic beverage containing liquor or wine plus a carbonated beverage, usually served with ice. [PJC]
4. jail; -- usually used in the form the cooler. [slang] [PJC]
4. an air conditioner. [PJC] cool-headed