The Collaborative International Dictionary of English v.0.48:

Prey \Prey\, v. i. [imp. & p. p. Preyed; p. pr. & vb. n.
   Preying.] [OF. preier, preer, L. praedari, fr. praeda. See
   Prey, n.]
   To take booty; to gather spoil; to ravage; to take food by
   violence.
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         More pity that the eagle should be mewed,
         While kites and buzzards prey at liberty. --Shak.
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   To prey on or To prey upon.
   (a) To take prey from; to despoil; to pillage; to rob.
       --Shak.
   (b) To seize as prey; to take for food by violence; to seize
       and devour. --Shak.
   (c) To wear away gradually; to cause to waste or pine away;
       as, the trouble preyed upon his mind. --Addison.
       [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Prey \Prey\, n. [OF. preie, F. proie, L. praeda, probably for
   praeheda. See Prehensile, and cf. Depredate,
   Predatory.]
   Anything, as goods, etc., taken or got by violence; anything
   taken by force from an enemy in war; spoil; booty; plunder.
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         And they brought the captives, and the prey, and the
         spoil, unto Moses, and Eleazar the priest. --Num. xxxi.
                                                  12.
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   2. That which is or may be seized by animals or birds to be
      devoured; hence, a person given up as a victim.
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            The old lion perisheth for lack of prey. --Job iv.
                                                  ii.
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            Already sees herself the monster's prey. --Dryden.
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   3. The act of devouring other creatures; ravage.
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            Hog in sloth, fox in stealth, . . . lion in prey.
                                                  --Shak.
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   Beast of prey, a carnivorous animal; one that feeds on the
      flesh of other animals.
      [1913 Webster]

WordNet (r) 3.0 (2006):

prey
    n 1: a person who is the aim of an attack (especially a victim
         of ridicule or exploitation) by some hostile person or
         influence; "he fell prey to muggers"; "everyone was fair
         game"; "the target of a manhunt" [syn: prey, quarry,
         target, fair game]
    2: animal hunted or caught for food [syn: prey, quarry]
    v 1: profit from in an exploitatory manner; "He feeds on her
         insecurity" [syn: prey, feed]
    2: prey on or hunt for; "These mammals predate certain eggs"
       [syn: raven, prey, predate]