Source : Webster's Revised Unabridged Dictionary (1913)

Snarl \Snarl\, v. t. [imp. & p. p. {Snarled}; p. pr. & vvb. n.
   {Snarling}.] [Etymol. uncertain.]
   To form raised work upon the outer surface of (thin metal
   ware) by the repercussion of a snarling iron upon the inner
   surface.

Snarling \Snarl"ing\,
   a. & n. from {Snarl}, v.

   {Snarling iron}, a tool with a long beak, used in the process
      of snarling. When one end is held in a vise, and the shank
      is struck with a hammer, the repercussion of the other
      end, or beak, within the article worked upon gives the
      requisite blow for producing raised work. See 1st {Snarl}.