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.

Source : WordNet®

snarled
     adj : tangled in knots or snarls; "a mass of knotted string";
           "snarled thread" [syn: {knotted}, {snarly}]