Source : Webster's Revised Unabridged Dictionary (1913)

Checkmate \Check"mate\, v. t. [imp. & p. p. {Checkmated}; p. pr.
   & vb. n. {Checkmating}.]
   1. (Chess) To check (an adversary's king) in such a manner
      that escape in impossible; to defeat (an adversary) by
      putting his king in check from which there is no escape.

   2. To defeat completely; to terminate; to thwart.

            To checkmate and control my just demands. --Ford.