Source : Webster's Revised Unabridged Dictionary (1913)

Lighter \Light"er\, n. [D. ligter, fr. ligt light. See {Light}
   not heavy.] (Naut.)
   A large boat or barge, mainly used in unloading or loading
   vessels which can not reach the wharves at the place of
   shipment or delivery.

   {Lighter screw} (Mach.), a screw for adjusting the distance
      between the stones in a grinding mill by raising or
      lowering the bridgetree.