The Collaborative International Dictionary of English v.0.48:

Plume \Plume\, v. t. [imp. & p. p. Plumed; p. pr. & vb. n.
   Pluming.] [Cf. F. plumer to pluck, to strip, L. plumare to
   cover with feathers.]
   1. To pick and adjust the plumes or feathers of; to dress or
      prink.
      [1913 Webster]

            Pluming her wings among the breezy bowers. --W.
                                                  Irving.
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   2. To strip of feathers; to pluck; to strip; to pillage;
      also, to peel. [Obs.] --Bacon. Dryden.
      [1913 Webster]

   3. To adorn with feathers or plumes. "Farewell the plumed
      troop." --Shak.
      [1913 Webster]

   4. To pride; to vaunt; to boast; -- used reflexively; as, he
      plumes himself on his skill. --South.
      [1913 Webster]

   Plumed adder (Zool.), an African viper (Vipera cornuta,
      syn. Clotho cornuta), having a plumelike structure over
      each eye. It is venomous, and is related to the African
      puff adder. Called also horned viper and hornsman.

   Plumed partridge (Zool.), the California mountain quail
      (Oreortyx pictus). See Mountain quail, under
      Mountain.
      [1913 Webster]

WordNet (r) 3.0 (2006):

plumed
    adj 1: having or covered with or abounding in plumes; "the
           plumed serpent"; "white-plumed egrets" [syn: plumed,
           plumy]
    2: having an ornamental plume or feathery tuft [syn: plumate,
       plumed, plumose]
    3: (of a knight's helmet) having a decorative plume [syn:
       crested, plumed]

Moby Thesaurus II by Grady Ward, 1.0:

31 Moby Thesaurus words for "plumed":
   adorned, beaded, bedecked, bedizened, befrilled, bejeweled,
   beribboned, bespangled, capped, crested, crowned, decked out,
   decorated, embellished, feathered, festooned, figured, flowered,
   garnished, headed, jeweled, ornamented, peaked, spangled, spangly,
   studded, tipped, topped, tricked out, trimmed, wreathed