Source : Webster's Revised Unabridged Dictionary (1913)

Vaticinate \Va*tic"i*nate\, v. i. & t. [L. vaticinatus, p. p. of
   vaticinari to prophesy, fr. vaticinus prophetical, fr. vates
   a prophet.]
   To prophesy; to foretell; to practice prediction; to utter
   prophecies.

Source : WordNet®

vaticinate
     v 1: predict or reveal through, or as if through, divine
          inspiration [syn: {prophesy}]
     2: foretell through or as if through the power of prophecy