The Collaborative International Dictionary of English v.0.48:

Jubilate \Ju`bi*la"te\, n. [L., imperat. of jubilare to shout
   for joy.]
   [1913 Webster]
   1. The third Sunday after Easter; -- so called because the
      introit is the 66th Psalm, which, in the Latin version,
      begins with the words, "Jubilate Deo."
      [1913 Webster]

   2. A name of the 100th Psalm; -- so called from its opening
      word in the Latin version.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Jubilate \Ju"bi*late\, v. i. [L. jubilatus, p. p. of jubilare.]
   To exult; to rejoice. [R.] --De Quincey.
   [1913 Webster]

WordNet (r) 3.0 (2006):

jubilate
    v 1: celebrate a jubilee
    2: to express great joy; "Who cannot exult in Spring?" [syn:
       exuberate, exult, rejoice, triumph, jubilate]