to begin fooling around with a female then when the pants come off you unexpectedly find that she has a very shitty ass crack, it doesnt bother the male and he commences to have anal sex
Doyle: "Dude oh my god, the other night I got that girl from the bar back to my apartment and found out she was Brown Trenching."

Brad: " Oh god man that is gross... What did you do?"

Doyle: " What do you mean gross??!!??"
by HansardSD July 13, 2010
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