Source : Webster's Revised Unabridged Dictionary (1913)

Gnarled \Gnarled\, a.
   Knotty; full of knots or gnarls; twisted; crossgrained.

         The unwedgeable and gnarl['e]d oak.      --Shak.

Gnarl \Gnarl\, v. i. [imp. & p. p. {Gnarled}; p. pr. & vb. n.
   {Gnarling}.] [From older gnar, prob. of imitative origin; cf.
   G. knarren, knurren. D. knorren, Sw. knorra, Dan. knurre.]
   To growl; to snarl.

         And wolves are gnarling who shall gnaw thee first.
                                                  --Shak.

Source : WordNet®

gnarled
     adj : used of old persons or old trees; covered with knobs or
           knots; "gnarled and knotted hands"; "a knobbed stick"
           [syn: {gnarly}, {knotted}, {knotty}, {knobbed}]