cool one's jets

cool one's jets

1. (informal) To become less excited, intense, or active; to exercise self-restraint.
   • 1999 April 7, Joyce Slaton, "Phantom Menace Book Tells All," Wired:

     Star Wars fans who positively can't cool their jets until the 19 May opening of Star Wars prequel The Phantom Menace need wait no longer than until early May.

   • 2004 Oct. 6, Kirk Honeycutt, "Taxi (film review)," The Hollywood Reporter:

     Belle's boyfriend Jesse (Henry Simmons) is left to cool his jets while his woman bangs around the New York area.

• calm down, chill, chill out, cool off, pull in one's horns, settle down