Source : Webster's Revised Unabridged Dictionary (1913)

Dishearten \Dis*heart"en\, v. t. [imp. & p. p. {Disheartened};
   p. pr. & vb. n. {Disheartening}.] [Pref. dis- + hearten.]
   To discourage; to deprive of courage and hope; to depress the
   spirits of; to deject.

         Regiments . . . utterly disorganized and disheartened.
                                                  --Macaulay.

   Syn: To dispirit; discourage; depress; deject; deter;
        terrify.

Source : WordNet®

disheartening
     adj : destructive of morale and self-reliance [syn: {demoralizing},
            {demoralising}, {dispiriting}]