C.O.O.I. is an abbreviation for Chime Out of it. Usually used in the context of someone 'chiming' into your conversation.

C.O.O.I. isn't pronounced in letters, it is pronounced like Coo-ee.
Person 1: "C.O.O.I. Bob!"

Person 2: Yeah CHIME OUT OF IT!
BOB: Ok.
by Muftasizer July 31, 2009
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