What does "backboard" mean?

Backboard: A board serving as the back part of anything, as of a wagon.

Additional senses

  1. 2.A thin stuff used for the backs of framed pictures, mirrors, etc.
  2. 3.A board attached to the rim of a water wheel to prevent the water from running off the floats or paddies into the interior of the wheel. W. Nicholson.
  3. 4.A board worn across the back to give erectness to the figure. Thackeray.

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