[1] : The Collaborative International Dictionary of English v.0.48

backboard \back"board`\, n. 2d back, n. + board.
   1913 webster
   1. a board which supports the back when one is sitting;
      specifically, the board athwart the after part of a boat.
      1913 webster

   2. a board serving as the back part of anything, as of a
      wagon.
      1913 webster

   3. a thin stuff used for the backs of framed pictures,
      mirrors, etc.
      1913 webster

   4. a board attached to the rim of a water wheel to prevent
      the water from running off the floats or paddles into the
      interior of the wheel. --w. nicholson.
      1913 webster

   5. a board worn across the back to give erectness to the
      figure. --thackeray.
      1913 webster

[2] : WordNet (r) 2.0

backboard
     n 1: a raised vertical board with basket attached; used to play
          basketball; "he banked the shot off the backboard" syn:
           basketball backboard
     2: a board used to support the back of someone or something
see also:
basketball backboard 

Backboard >> B Words
Backboard, definition of term: Backboard
backboard_pag1.html