The Collaborative International Dictionary of English v.0.48:

Dispirit \Dis*pir"it\, v. t. [imp. & p. p. Dispirited; p. pr.
   & vb. n. Dispiriting.] [Pref. dis- + spirit.]
   1. To deprive of cheerful spirits; to depress the spirits of;
      to dishearten; to discourage.
      [1913 Webster]

            Not dispirited with my afflictions.   --Dryden.
      [1913 Webster]

            He has dispirited himself by a debauch. --Collier.
      [1913 Webster]

   2. To distill or infuse the spirit of. [Obs. or R.]
      [1913 Webster]

            This makes a man master of his learning, and
            dispirits the book into the scholar.  --Fuller.

   Syn: To dishearten; discourage; deject; damp; depress; cast
        down; intimidate; daunt; cow.
        [1913 Webster]

WordNet (r) 3.0 (2006):

dispirit
    v 1: lower someone's spirits; make downhearted; "These news
         depressed her"; "The bad state of her child's health
         demoralizes her" [syn: depress, deject, cast down,
         get down, dismay, dispirit, demoralize,
         demoralise] [ant: elate, intoxicate, lift up, pick
         up, uplift]