coolest

Adjective

cool (comparative cooler, superlative coolest)

1. Of a mildly low temperature.
   • I like cool weather the most 'cause it's not too hot to wear a jacket but I won't be too cold in my shorts.

   Synonyms:

   chilly

   Antonyms:

   lukewarm, tepid, warm

2. Allowing or suggesting heat relief.
   • Linen has made cool and breathable clothing for millennia.
3. Of a color, in the range of violet to green.
   • If you have a reddish complexion, you should mainly wear cool colors.

   Antonyms:

   warm

4. Not showing emotion; calm and in control of oneself.
   • Be cool. There's no need to panic.

   Synonyms:

   distant, phlegmatic, standoffish, unemotional

   Antonyms:

   passionate

5. Unenthusiastic; lukewarm; skeptical.
   • His proposals had a cool reception.

   Synonyms:

   chilly, lukewarm, tepid

   Antonyms:

   warm

6. (obsolete) Calmly audacious.
   • Its cool stare of familiarity was intolerable.1850, Nathaniel Hawthorne, “Hester at her Needle”, in The Scarlet Letter, a Romance, Boston, Mass.: Ticknor, Reed, and Fields, →OCLC

See all 26 meanings of cool