Source : Webster's Revised Unabridged Dictionary (1913)

Vellicate \Vel"li*cate\, v. t. [imp. & p. p. {Vellicated}; p.
   pr. & vb. n. {Vellicating}.] [L. vellicatus, p. p. of
   vellicare to twitch, fr. vellere to pluck, pull.]
   To twitch; to cause to twitch convulsively.

         Convulsions, arising from something vellicating a nerve
         in its extremity, are not very dangerous. --Arbuthnot.

Vellicate \Vel"li*cate\, v. i.
   To move spasmodically; to twitch; as, a nerve vellicates.

Source : WordNet®

vellicate
     v 1: touch (a body part) lightly so as to excite the surface
          nerves and cause uneasiness, laughter, or spasmodic
          movements [syn: {tickle}, {titillate}]
     2: irritate as if by a nip, pinch, or tear; "smooth surfaces
        can vellicate the teeth"; "the pain is as if sharp points
        pinch your back" [syn: {pinch}]