Definitions by erica elaine

back cleavage 

when a fat lady (particularly old), wears a swimsuit or bra that is too tight in the back and it squishes the back fat together to give the illusion that there are boobs on their back.

Lifeguard 1: "that old lady is large"

Lifeguard 2: "yeah man, look at her back cleavage, it's impressive."

back cleavage by erica elaine April 23, 2006