Source : Webster's Revised Unabridged Dictionary (1913)

Knab \Knab\, v. t. [imp. & p. p. {Knabbed}; p. pr. & vb. n.
   {Knabbing}.] [See {Nab}, v. t., and cf. {Knap}, v. t.]
   1. To seize with the teeth; to gnaw. ``Knabbing crusts.''
      [Obs.] --L'Estrange.

   2. To nab. See {Nab}, v. t. [Colloq.]