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

Despair
Written in 1935 and heavily revised in 1965, DESPAIR is a witty puzzle of a murder mystery ` la Nabokov, in which the protagonist, Hermann Hermann, decides to escape his mundane existence by faking his own death--a feat he accomplishes by killing his double -- or, at least, his absurd conception of what his double might be.

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1. \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}.
   

2. \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.
   

3. \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.
   2. That which is despaired of. ``The mere despair of surgery
      he cures.'' --Shak.
   Syn: Desperation; despondency; hopelessness.