The Collaborative International Dictionary of English v.0.48:

Stalk \Stalk\, v. i. [imp. & p. p. Stalked (st[add]kt); p. pr.
   & vb. n. Stalking.] [AS. staelcan, stealcian to go slowly;
   cf. stealc high, elevated, Dan. stalke to stalk; probably
   akin to 1st stalk.]
   1. To walk slowly and cautiously; to walk in a stealthy,
      noiseless manner; -- sometimes used with a reflexive
      pronoun. --Shak.
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            Into the chamber he stalked him full still.
                                                  --Chaucer.
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            [Bertran] stalks close behind her, like a witch's
            fiend,
            Pressing to be employed.              --Dryden.
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   2. To walk behind something as a screen, for the purpose of
      approaching game; to proceed under cover.
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            The king . . . crept under the shoulder of his led
            horse; . . . "I must stalk," said he. --Bacon.
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            One underneath his horse, to get a shoot doth stalk.
                                                  --Drayton.
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   3. To walk with high and proud steps; -- usually implying the
      affectation of dignity, and indicating dislike. The word
      is used, however, especially by the poets, to express
      dignity of step.
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            With manly mien he stalked along the ground.
                                                  --Dryden.
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            Then stalking through the deep,
            He fords the ocean.                   --Addison.
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            I forbear myself from entering the lists in which he
            has long stalked alone and unchallenged. --Merivale.
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WordNet (r) 3.0 (2006):

stalking
    n 1: a hunt for game carried on by following it stealthily or
         waiting in ambush [syn: stalk, stalking, still hunt]
    2: the act of following prey stealthily [syn: stalk,
       stalking]

Moby Thesaurus II by Grady Ward, 1.0:

65 Moby Thesaurus words for "stalking":
   chase, chevy, chivy, clandestine behavior, clandestinity, coursing,
   covertness, cynegetics, dogging, domiciliary visit, dragnet,
   exploration, falconry, follow, follow-up, following, forage,
   fox hunting, frisk, furtiveness, gunning, hawking, house-search,
   hue and cry, hunt, hunting, perquisition, posse, probe,
   prosecution, prowl, prowling, pursuance, pursuing, pursuit, quest,
   ransacking, rummage, search, search party, search warrant,
   search-and-destroy operation, searching, seeking, shadowing,
   shiftiness, shikar, shooting, slinkiness, slyness, sneakiness,
   sport, sporting, stalk, stealth, stealthiness, still hunt,
   surreptitiousness, tracking, tracking down, trailing, turning over,
   underground activity, underhand dealing, venery