keep one’s cool

keep (one's) cool

To maintain control of one's composure, temper, or nerve in a given situation. He really kept his cool when the waiter dropped his food. I tried to keep my cool during the interview, but I was extremely nervous the whole time.
See also: cool, keep
Farlex Dictionary of Idioms.

keep one’s cool

tv. to remain calm and in control. (see also keep cool. Compare this with lose one’s cool.) It’s hard to keep your cool when you’ve been cheated.
See also: cool, keep
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • keep (one's) cool
  • keep cool
  • keep one's cool
  • keep your cool
  • keep/lose your cool
  • lose (one's) cool
  • lose cool
  • lose one’s cool
  • lose one's cool
  • lose your cool