Source : Webster's Revised Unabridged Dictionary (1913)

Planer \Plan"er\, n.
   1. One who, or that which, planes; a planing machine; esp., a
      machine for planing wood or metals.

   2. (Print.) A wooden block used for forcing down the type in
      a form, and making the surface even. --Hansard.

   {Planer centers}. See under {Center}.

Source : WordNet®

planer
     n : a power tool for smoothing or shaping wood [syn: {plane}, {planing
         machine}]