Source : Webster's Revised Unabridged Dictionary (1913)

Whirlbat \Whirl"bat`\, n.
   Anything moved with a whirl, as preparatory for a blow, or to
   augment the force of it; -- applied by poets to the cestus of
   ancient boxers.

         The whirlbat and the rapid race shall be Reserved for
         C[ae]sar.                                --Dryden.