"Cool it" can refer to either the standard English use (instruction to chill) or the colloquial which indicates that someone should calm down or otherwise refrain from an argument.
Example sentences...
"'This movement, she felt, must be turning of the earth, rotating the on its axis, traveling the elliptic course about the sun.'".
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page 65 A Wrinkle in Time by Madeleine L'Engle
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