flappa-jacka 

noun: descibes a smallish breast that basically lies flat on one's chest in a saggy sort of way. not cute.

"oh my god--my old boss had the scariest tits--there were so flappa-jacka."

flappa-jacka by perkin March 11, 2003

flappy jack

When a fat chick rolls her arm fat (or flaps) over a man's dick and proceeds to jack him off

"Did you get sex last night?"

"No, I just got a flappy jack."

flappy jack by TheOneAndOnlyHippie December 8, 2014