1. Cool Your Jets Link

: To advise caution when someone is acting impulsively out of enthusiasm (e.g., "Cool your jets, Sarah. Make sure you have the job offer in writing first.").

: One of its earliest recorded uses is in the 1952 novel Stand by for Mars! from the Tom Corbett, Space Cadet series, where a character is told, "Cool your jets, space creep!". 1. Cool Your Jets

or Take a chill pill : Modern, very informal ways to say the same thing. : To advise caution when someone is acting

: Specifically used when someone's anger is "boiling over". Keep your shirt on : An older idiom for staying calm. Pop Culture Connections "Cool your jets