To be one who cums excessively.
Such as a braggart who brags excessively.
But in this case you're cumming excessively.
Guy 1: Dude, I came on that girls face last night!
Guy 2: You're such a fucking Cummart.
Guy 1: *Donkey Punches Guy 2*
by Eatin Yer Soulz June 2, 2008
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