1 definition by erica elaine

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."
by erica elaine April 5, 2006
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