An acronym for My Body Is Ready. Something you say when you see someone who is overwhelmingly attractive and would like to partake in sexual activities with them.
Person 1: Have you seen this picture of Cristiano Ronaldo? *shows picture*
Person 2: MY BODY IS READY.

or when not appropriate to say "My body is ready" out loud, one would say "MBIR."
by wet paint June 14, 2011
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