The Collaborative International Dictionary of English v.0.48:

Showy \Show"y\, a. [Compar. Showier; superl. Showiest.]
   Making a show; attracting attention; presenting a marked
   appearance; ostentatious; gay; gaudy.
   [1913 Webster]

         A present of everything that was rich and showy.
                                                  --Addison.
   [1913 Webster]

   Syn: Splendid; gay; gaudy; gorgeous; fine; magnificent;
        grand; stately; sumptuous; pompous.
        [1913 Webster]

WordNet (r) 3.0 (2006):

showy
    adj 1: marked by ostentation but often tasteless; "a cheap showy
           rhinestone bracelet"; "a splashy half-page ad" [syn:
           flamboyant, showy, splashy]
    2: displaying brilliance and virtuosity
    3: (used especially of clothes) marked by conspicuous display
       [syn: flashy, gaudy, jazzy, showy, sporty]
    4: superficially attractive and stylish; suggesting wealth or
       expense; "a glossy TV series" [syn: glossy, showy]

Moby Thesaurus II by Grady Ward, 1.0:

90 Moby Thesaurus words for "showy":
   Byzantine, Gongoresque, Johnsonian, affected, arabesque, baroque,
   bedizened, big-sounding, brave, bravura, braw, chichi, conspicuous,
   convoluted, daring, dashing, declamatory, dressy, elaborate,
   elevated, euphuistic, exhibitionistic, fancy, flamboyant, flaming,
   flashing, flashy, flaunting, florid, frilly, frothy, fulsome,
   fussy, gallant, garish, gaudy, gay, glittering, gorgeous,
   grandiloquent, grandiose, grandisonant, high-flowing, high-flown,
   high-flying, high-sounding, highfalutin, inkhorn, intricate,
   jaunty, jazzy, labyrinthine, lexiphanic, lofty, lurid, luxurious,
   magniloquent, meretricious, opulent, ornate, orotund, ostentatious,
   overdone, overelaborate, overinvolved, overwrought, peacockish,
   peacocky, pedantic, pompous, pretentious, rakish, resplendent,
   rhetorical, rococo, sensational, sensationalistic, sententious,
   show-off, snazzy, sonorous, splashy, splurgy, sporty, stilted,
   sumptuous, swank, tall, tawdry, tortuous