Source : Webster's Revised Unabridged Dictionary (1913)

Hallucinate \Hal*lu"ci*nate\, v. i. [L. hallucinatus,
   alucinatus, p. p. of hallucinari, alucinari, to wander in
   mind, talk idly, dream.]
   To wander; to go astray; to err; to blunder; -- used of
   mental processes. [R.] --Byron.

Source : WordNet®

hallucinate
     v : perceive what is not there; have illusions