The Collaborative International Dictionary of English v.0.48:

Attire \At*tire"\, v. t. [imp. & p. p. Attired; p. pr. & vb.
   n. Attiring.] [OE. atiren to array, dispose, arrange, OF.
   atirier; [`a] (L. ad) + F. tire rank, order, row; of Ger.
   origin: cf. As. tier row, OHG. ziar[imac], G. zier, ornament,
   zieren to adorn. Cf. Tire a headdress.]
   To dress; to array; to adorn; esp., to clothe with elegant or
   splendid garments.
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         Finely attired in a robe of white.       --Shak.
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         With the linen miter shall he be attired. --Lev. xvi.
                                                  4.
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The Collaborative International Dictionary of English v.0.48:

Attire \At*tire"\, n.
   1. Dress; clothes; headdress; anything which dresses or
      adorns; esp., ornamental clothing.
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            Earth in her rich attire.             --Milton.
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            I 'll put myself in poor and mean attire. --Shak.
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            Can a maid forget her ornament, or a bride her
            attire?                               --Jer. ii. 32.
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   2. The antlers, or antlers and scalp, of a stag or buck.
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   3. (Bot.) The internal parts of a flower, included within the
      calyx and the corolla. [Obs.] --Johnson.
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WordNet (r) 3.0 (2006):

attire
    n 1: clothing of a distinctive style or for a particular
         occasion; "formal attire"; "battle dress" [syn: attire,
         garb, dress]
    v 1: put on special clothes to appear particularly appealing and
         attractive; "She never dresses up, even when she goes to
         the opera"; "The young girls were all fancied up for the
         party" [syn: overdress, dress up, fig out, fig up,
         deck up, gussy up, fancy up, trick up, deck out,
         trick out, prink, attire, get up, rig out, tog
         up, tog out] [ant: dress down, underdress]

Moby Thesaurus II by Grady Ward, 1.0:

72 Moby Thesaurus words for "attire":
   accouter, apparel, appoint, arm, array, bedeck, bedizenment,
   bedrape, bundle up, clad, clothe, clothes, clothing, costume, deck,
   dight, drape, drapery, dress, dressing, dud, duds, enclothe, endue,
   enrobe, enshroud, envelop, enwrap, equip, fashion, fatigues,
   feathers, fig, garb, garment, garments, gear, guise, habiliment,
   habiliments, habilitate, habit, invest, investiture, investment,
   lap, linen, muffle up, outfit, rag out, rags, raiment, robe, robes,
   sheathe, shroud, sportswear, style, swaddle, swathe, things,
   threads, tire, togs, toilette, trim, vestment, vesture, wear,
   wearing apparel, wrap, wrap up