Source : Webster's Revised Unabridged Dictionary (1913)

Despair \De*spair"\, v. i. [imp. & p. p. {Despaired}; p. pr. &
   vb. n. {Despairing}.] [OE. despeiren, dispeiren, OF.
   desperer, fr. L. desperare; de- + sperare to hope; akin to
   spes hope, and perh. to spatium space, E. space, speed; cf.
   OF. espeir hope, F. espoir. Cf. {Prosper}, {Desperate}.]
   To be hopeless; to have no hope; to give up all hope or
   expectation; -- often with of.

         We despaired even of life.               --2 Cor. i. 8.

         Never despair of God's blessings here.   --Wake.

   Syn: See {Despond}.

Despair \De*spair"\, v. t.
   1. To give up as beyond hope or expectation; to despair of.
      [Obs.]

            I would not despair the greatest design that could
            be attempted.                         --Milton.

   2. To cause to despair. [Obs.] --Sir W. Williams.

Despair \De*spair"\, n. [Cf. OF. despoir, fr. desperer.]
   1. Loss of hope; utter hopelessness; complete despondency.

            We in dark dreams are tossing to and fro, Pine with
            regret, or sicken with despair.       --Keble.

            Before he [Bunyan] was ten, his sports were
            interrupted by fits of remorse and despair.
                                                  --Macaulay.

Source : WordNet®

despair
     n 1: a state in which everything seems wrong and will turn out
          badly; "they were rescued from despair at the last
          minute" [syn: {desperation}]
     2: the feeling that everything is wrong and nothing will turn
        out well [ant: {hope}]
     v : abandon hope; give up hope; lose heart; "Don't despair--help
         is on the way!" [ant: {hope}]