Source : Webster's Revised Unabridged Dictionary (1913)

Forlese \For*lese"\, v. t. [p. p. {Forlore}, {Forlorn}.] [OE.
   forlesen. See {Forlorn}.]
   To lose utterly. [Obs.] --haucer.

Forlorn \For*lorn"\, a. [OE., p. p. of forlesen to lose utterly,
   AS. forle['o]san (p. p. forloren); pref. for- + le['o]san (in
   comp.) to lose; cf. D. verliezen to lose, G. verlieren, Sw.
   f["o]rlora, Dan. forloren, Goth. fraliusan to lose. See
   {For-}, and {Lorn}, a., {Lose}, v. t.]
   1. Deserted; abandoned; lost.

            Of fortune and of hope at once forlorn. --Spenser.

            Some say that ravens foster forlorn children.
                                                  --Shak.

   2. Destitute; helpless; in pitiful plight; wretched;
      miserable; almost hopeless; desperate.

            For here forlorn and lost I tread.    --Goldsmith.

            The condition of the besieged in the mean time was
            forlorn in the extreme.               --Prescott.

            She cherished the forlorn hope that he was still
            living.                               --Thomson.

   {A forlorn hope} [D. verloren hoop, prop., a lost band or
      troop; verloren, p. p. of verliezen to lose + hoop band;
      akin to E. heap. See {For-}, and {Heap}.] (Mil.), a body
      of men (called in F. enfants perdus, in G. verlornen
      posten) selected, usually from volunteers, to attempt a
      breach, scale the wall of a fortress, or perform other
      extraordinarily perilous service; also, a desperate case
      or enterprise.

   Syn: Destitute, lost; abandoned; forsaken; solitary;
        helpless; friendless; hopeless; abject; wretched;
        miserable; pitiable.

Forlorn \For*lorn"\, n.
   1. A lost, forsaken, or solitary person.

            Forced to live in Scotland a forlorn. --Shak.

   2. A forlorn hope; a vanguard. [Obs.]

            Our forlorn of horse marched within a mile of the
            enemy.                                --Oliver
                                                  Cromvell.

Source : WordNet®

forlorn
     adj 1: pitiable in circumstances especially through abandonment;
            "desolate and despairing"; "left forlorn" [syn: {desolate},
             {godforsaken}, {lorn}]
     2: marked by or showing hopelessness; "the last forlorn
        attempt"; "a forlorn cause"