Definition of backboards:
(n) :
(basketball) The flat vertical surface to which the basket is attached.
(n) :
(tennis) A flat vertical wall with the image of a tennis net drawn or painted on it, designed to practice hitting against such that the ball rebounds.
(n) :
(medicine) A spine board.
(v) :
(medicine, transitive) To place (a patient) on a spine board.
(n) :
A board placed at the back of a cart, boat, behind a signal, etc.
(n) :
(nautical) The port or larboard side of a ship