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Adj. when you have a half boner and stick it in anyways

Things that can cause flappy dunk: excessive alcohol, non-attractive partner, mood-killing conversation, general inadequacy, among other. Please see your doctor if this happens too often.
Bro: "So how was your night? Did you get it in?"
You: "Yeah..but it was a flappy dunk, too much beer last night"
by Anthonyguy July 30, 2017
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