The Collaborative International Dictionary of English v.0.48:

Feat \Feat\ (f[=e]t), n. [OE. fet, OF. fet, fait, F. fait,
   factum, fr. L. facere, factum, to make or do. Cf. Fact,
   Feasible, Do.]
   1. An act; a deed; an exploit.
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            The warlike feats I have done.        --Shak.
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   2. A striking act of strength, skill, or cunning; a trick;
      as, feats of horsemanship, or of dexterity.
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The Collaborative International Dictionary of English v.0.48:

Feat \Feat\, v. t.
   To form; to fashion. [Obs.]
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         To the more mature,
         A glass that feated them.                --Shak.
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The Collaborative International Dictionary of English v.0.48:

Feat \Feat\, a. [Compar. Feater; superl. Featest.] [F. fait
   made, shaped, fit, p. p. of faire to make or do. See Feat,
   n.]
   Dexterous in movements or service; skillful; neat; nice;
   pretty. [Archaic]
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         Never master had a page . . . so feat.   --Shak.
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         And look how well my garments sit upon me
         Much feater than before.                 --Shak.
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WordNet (r) 3.0 (2006):

feat
    n 1: a notable achievement; "he performed a great feat"; "the
         book was her finest effort" [syn: feat, effort,
         exploit]

Moby Thesaurus II by Grady Ward, 1.0:

58 Moby Thesaurus words for "feat":
   accomplished fact, accomplishment, achievement, act, acta, action,
   adventure, aristeia, attainment, blow, bold stroke, conquest,
   consummation, coup, dealings, deed, doing, doings, effort, emprise,
   endeavor, enterprise, execution, exploit, fait accompli, gest, go,
   hand, handiwork, heroic act, job, maneuver, master stroke,
   masterpiece, masterwork, measure, move, operation, overt act,
   passage, performance, proceeding, production, res gestae, step,
   stroke, stunt, thing, thing done, tour de force, transaction,
   triumph, turn, undertaking, venture, victory, work, works