The Collaborative International Dictionary of English v.0.48:

Uncolored \Uncolored\
   See colored.

WordNet (r) 3.0 (2006):

uncolored
    adj 1: without color; "pure water is uncolored" [syn:
           uncolored, uncoloured] [ant: colored, colorful,
           coloured]
    2: not artificially colored or bleached; "unbleached blonde
       hair"; "her hair is uncolored"; "undyed cotton" [syn:
       unbleached, uncolored, undyed]

Moby Thesaurus II by Grady Ward, 1.0:

126 Moby Thesaurus words for "uncolored":
   achromatic, achromic, anemic, ashen, ashy, authentic, bled white,
   bloodless, bona fide, cadaverous, candid, card-carrying,
   chloranemic, colorless, dead, deadly pale, deathly pale, dim,
   dimmed, dingy, dinkum, discolored, dispassionate, dull, equal,
   equitable, etiolated, exsanguinated, exsanguine, exsanguineous,
   faded, faint, fallow, flat, following the letter, genuine, ghastly,
   good, gray, haggard, honest, honest-to-God, hueless, hypochromic,
   impartial, inartificial, just, lackluster, lawful, leaden,
   legitimate, lifelike, literal, livid, lurid, lusterless, mat,
   mealy, muddy, natural, naturalistic, neutral, objective, original,
   pale, pale as death, pale-faced, pallid, pasty, pure, real,
   realistic, rightful, sallow, sickly, simon-pure, simple, sincere,
   sterling, sure-enough, tallow-faced, toneless, true to life,
   true to nature, true to reality, unadulterated, unaffected,
   unassumed, unassuming, unbiased, unconcocted, uncopied,
   uncounterfeited, undisguised, undisguising, undistorted,
   unexaggerated, unfabricated, unfanciful, unfeigned, unfeigning,
   unfictitious, unflattering, unimagined, unimitated, uninvented,
   unprejudiced, unpretended, unpretending, unqualified, unromantic,
   unsimulated, unspecious, unsynthetic, unvarnished, verbal,
   verbatim, veridical, verisimilar, wan, washed-out, waxen, weak,
   whey-faced, white, word-for-word