The process of knocking all of one's teeth out, and then proceeding to force them to slurp on your penis, using their gums, which formerly had teeth, but longer have teeth, because you just knocked them all out.

Note: "d" refers to dick
Guy 1: Hey, your sisters cute

Guy 2: Yeah, maybe before she lost all her teeth and gummed my d

Guy 1: yo, can I gum the d too?
by DJ Sketch February 1, 2009
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