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

dartboard \dartboard\, dart board \dart board\n.
   a circular board of wood or cork used as the target in the
   game of darts. it may have any of several patterns on it,
   such as concentric circles, or a central circle with rays.
   wordnet 1.5 +pjc

[2] : WordNet (r) 2.0

dartboard
     n : a circular board of wood or cork used as the target in the
         game of darts syn: dart board
see also:
dart board 

Dartboard >> D Words
Dartboard, definition of term: Dartboard
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