When you ejaculate a massive load on someone in a repeating linear pattern to form a perfectly large rectangular patch, then top it off with sprinkles, similar to the frosting of the well known American snack Poptarts.
Guy 1: Dude, after not seeing her for the last month, I can't wait to Cumtart my girlfriend when she gets back from study abroad.
Guy 2: Totally bro, last week I put a bowl of sprinkles on the night stand and when i was about to cum, I asked my GF to pass the sprinkles and yelled "1 Cumtart coming up" while i busted on her and threw a fist of sprinkles all over her stomach.
(n). A hat or any head covering that someone places on their head. Also relating to a condom for one's penis.
Bryan: Bro where'd you get that awesome dome cap?
Mike: The one with the lakers logo on it? It's dope huh?! I got it from the hat store down the street
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Mike: Bro be sure you put that dome cap on before you do your thing with that girl
Bryan: You're right, I don't want to be a daddy right now