keep cool keep cool {v. phr.} Remain calm; remain unexcited. The main thing to remember in an emergency situation is to not lose one's head and keep cool. Categories: add yours {v. phr.} Source: A Dictionary of American Idioms by A. Makkai, M.T. Boatner, J.E. Gates © 2024 » In RussianTo section: K Subscribe to: American IdiomsIdioms feedEnglish languageHome page and general feed Discuss