cool (Noun) — The quality of being at a refreshingly low temperature. ex. "the cool of early morning"
cool (Noun) — Great coolness and composure under strain. ex. "keep your cool"
cool (Verb) — Make cool or cooler. ex. "cool the food" ex. "cool down the food"
cool (Verb) — Lose heat. ex. "The air cooled considerably after the thunderstorm"
cool (Verb) — Lose intensity. ex. "His enthusiasm cooled considerably"
cool (Adjective) — Neither warm nor very cold; giving relief from heat. ex. "a cool autumn day" ex. "a cool room" ex. "cool summer dresses" ex. "cool drinks" ex. "a cool breeze"
cool (Adjective) — Marked by calm self-control (especially in trying circumstances); unemotional. ex. "play it cool" ex. "keep cool"
cool (Adjective) — (colour) inducing the impression of coolness; used especially of greens and blues and violets. ex. "cool greens and blues and violets"
cool (Adjective) — Psychologically cool and unenthusiastic; unfriendly, unresponsive or showing dislike. ex. "relations were cool and polite" ex. "a cool reception" ex. "cool to the idea of higher taxes"
cool (Adjective) — (used of a number or sum) without exaggeration or qualification. ex. "a cool million bucks"
cool (Adjective) — Fashionable and attractive at the time; often skilled or socially adept. ex. "he's a cool dude" ex. "that's cool" ex. "Mary's dress is really cool" ex. "it's not cool to arrive at a party too early"