The Collaborative International Dictionary of English v.0.48:

Encourage \En*cour"age\ (?; 48), v. t. [imp. & p. p.
   Encouraged (?; 48); p. pr. & vb. n. Encouraging.] [F.
   encourager; pref. en- (L. in) + courage courage. See
   Courage.]
   To give courage to; to inspire with courage, spirit, or hope;
   to raise, or to increase, the confidence of; to animate;
   enhearten; to incite; to help forward; -- the opposite of
   discourage.
   [1913 Webster]

         David encouraged himself in the Lord.    --1 Sam. xxx.
                                                  6.

   Syn: To embolden; inspirit; animate; enhearten; hearten;
        incite; cheer; urge; impel; stimulate; instigate;
        countenance; comfort; promote; advance; forward;
        strengthen.
        [1913 Webster]

WordNet (r) 3.0 (2006):

encourage
    v 1: contribute to the progress or growth of; "I am promoting
         the use of computers in the classroom" [syn: promote,
         advance, boost, further, encourage]
    2: inspire with confidence; give hope or courage to [ant:
       discourage]
    3: spur on; "His financial success encouraged him to look for a
       wife"