1 definition by Eric Big Cock Graack

When a grandmother-like figure takes out her dentures and gives a man head, sliding his cock between her gums. Upon the mans cumming, the granny puts her dentures back in and bites off his dick.
Steve: Dude, Mike, your grandma Phyllis gave me the granny lockjaw last night.
Mike: I'm sorry man, I always knew she was senile...
by Eric Big Cock Graack July 2, 2011
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