The Collaborative International Dictionary of English v.0.48:

Stoop \Stoop\, v. i. [imp. & p. p. Stooped; p. pr. & vb. n.
   Stooping.] [OE. stoupen; akin to AS. st?pian, OD. stuypen,
   Icel. st[=u]pa, Sw. stupa to fall, to tilt. Cf 5th Steep.]
   1. To bend the upper part of the body downward and forward;
      to bend or lean forward; to incline forward in standing or
      walking; to assume habitually a bent position.
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   2. To yield; to submit; to bend, as by compulsion; to assume
      a position of humility or subjection.
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            Mighty in her ships stood Carthage long, . . .
            Yet stooped to Rome, less wealthy, but more strong.
                                                  --Dryden.
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            These are arts, my prince,
            In which your Zama does not stoop to Rome.
                                                  --Addison.
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   3. To descend from rank or dignity; to condescend. "She
      stoops to conquer." --Goldsmith.
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            Where men of great wealth stoop to husbandry, it
            multiplieth riches exceedingly.       --Bacon.
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   4. To come down as a hawk does on its prey; to pounce; to
      souse; to swoop.
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            The bird of Jove, stooped from his aery tour,
            Two birds of gayest plume before him drove.
                                                  --Milton.
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   5. To sink when on the wing; to alight.
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            And stoop with closing pinions from above. --Dryden.
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            Cowering low
            With blandishment, each bird stooped on his wing.
                                                  --Milton.
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   Syn: To lean; yield; submit; condescend; descend; cower;
        shrink.
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WordNet (r) 3.0 (2006):

stooped
    adj 1: having the back and shoulders rounded; not erect; "a
           little oldish misshapen stooping woman" [syn: hunched,
           round-backed, round-shouldered, stooped,
           stooping, crooked]

Moby Thesaurus II by Grady Ward, 1.0:

26 Moby Thesaurus words for "stooped":
   couchant, crouched, debased, depressed, flat, knee-high,
   knocked flat, laid low, low, low-built, low-hung, low-level,
   low-leveled, low-lying, low-set, low-statured, neap, prone,
   recumbent, runty, short, squat, squatty, stumpy, supine,
   unelevated