Source : Webster's Revised Unabridged Dictionary (1913)

Trimming \Trim"ming\,
   a. from {Trim}, v.

         The Whigs are, essentially, an inefficient, trimming,
         halfway sort of a party.                 --Jeffrey.

   {Trimming joist} (Arch.), a joist into which timber trimmers
      are framed; a header. See {Header}. --Knight.