Under arm flab, or fat. When older women win during Bingo games, they throw their hands in the air saying "I got a bingo!!!", flapping their arms (and underarms) wildly about in their excitement. Thus causing the wind movement from their "bingo flappers" to eradicate all other bingo players, bingo cards. Game, Set, Match.
" How do I get rid of these Bingo Flappers under my arms?"

" That girl has some serious Bingo Flapping going on over there".

"My god honey, Kristie alley has huge bingo flappers. She must be able to fly around the world!"
by Ironsoulx August 5, 2009
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