It means that your underwear and pants have recessed into the butt crack and it has formed a noticeable line in said clothing, viewable by all.
Dude 1: Damn dude, get that dog out the meathouse!
Dude 2: Well quit looking.
by maddizzletwentytwizzle November 03, 2007
Get the get that dog out the meathouse mug.