the woman that you take sailing with you whose main purpose is to ornament the foredeck by wearing a bikini and taking the top off to sunbathe. Really good deck bunnies shave their beaver before they arrive at dockside, and they take off their top and their bottom. See also rudder slut. Deck bunnies don't have to fuck the captain but its nice if they do, its usually a long swim to shore if they decide "no"
Two bad weekends in a row, first one it rained both days and the deck bunny wouldn't fuck. Next one, it was sunny but the deck bunny didn't shave, then got her period, then was too seasick to blow me down.