cool
blow your cool lose your composure; become angry or agitated. informal
cool as a cucumber perfectly cool or self-possessed.
2013DVD Verdict Crenna looks like he does in most of his movies: cool as a cucumber because he's got his shit together, a guy who ain't afraid to take charge when Ashland begins to show signs he's gone bonkers.
cool it behave in a less excitable way. informal
cool your heels: seeheel.
lose your cool lose control of your temper or emotions. informal
play it cool make an effort to be or appear to be calm and unemotional. informal
too cool for school very cool or fashionable. informal