The look, outline or shape of a girl's vulva as seen usually through thin clothing when they bend over, however it can also be a naked vulva, or upside down naked vulva when a girl bends over. WilburbootybuttpussySkipperjack
This word is usually used by an excited male seeing the Wilbur and calling out "Wiiiiillllbbbbuuuurrrr" as did the horse in the 1960's TV show Mr. Ed did with a whinnying horse sound. Or said like:"Wow, did you see that Wilbur?" Seeing a Wilbur can make a guy very excited and want to call out "Wilbur!" Going to places and events that might increase the chance of seeing a Wilbur is called "Wilburing" like at the beach or girls vollyball game.