The Collaborative International Dictionary of English v.0.48:

Misty \Mist"y\ (m[i^]st"[y^]), a. [Compar. Mistier
   (m[i^]st"[i^]*[~e]r); superl. Mistiest.] [AS. mistig. See
   Mist. In some senses misty has been confused with mystic.]
   1. Accompanied with mist; characterized by the presence of
      mist; obscured by, or overspread with, mist; as, a misty
      morning; misty weather; misty mountains; a misty
      atmosphere.
      [1913 Webster]

   2. Obscured as if by mist; dim; obscure; clouded; as, misty
      sight; to peer into the misty future.
      [1913 Webster]

            The more I muse therein [theology],
            The mistier it seemeth.               --Piers
                                                  Plowman.
      [1913 Webster]

WordNet (r) 3.0 (2006):

misty
    adj 1: filled or abounding with fog or mist; "a brumous October
           morning" [syn: brumous, foggy, hazy, misty]
    2: wet with mist; "the misty evening"

Moby Thesaurus II by Grady Ward, 1.0:

149 Moby Thesaurus words for "misty":
   addlebrained, addled, addleheaded, addlepated, airy, amorphic,
   amorphous, anarchic, attenuate, attenuated, baggy, beclouded,
   befuddled, blear, bleared, bleary, blind, blinding, blobby,
   blurred, blurry, boyish, cat-and-doggish, chaotic, characterless,
   clear as mud, cloudy, confused, dark, delicate, diaphanous,
   diluted, dim, disorderly, drippy, driving, drizzling, drizzly,
   drumming, ethereal, faint, featureless, feeble, filmy, fine,
   fine-drawn, finespun, flimsy, fogged, foggy, formless, frail,
   fuddlebrained, fuddled, fuzzy, gauzy, girlish, gossamer, gracile,
   half-seen, half-visible, hazy, ill-defined, in a fog, in a muddle,
   inchoate, inconspicuous, indecisive, indefinite, indeterminate,
   indistinct, indistinguishable, inform, insubstantial,
   kaleidoscopic, lacy, light, low-profile, lumpen, merely glimpsed,
   misted, misty-moisty, mizzly, muddled, muddleheaded, muddy, murky,
   muzzy, nebulous, nondescript, obscure, opaque, orderless,
   out of focus, pale, papery, pea-soupy, pelting, pluvial, pluviose,
   pluvious, pouring, puzzleheaded, rainy, rare, rarefied,
   semivisible, shadowy, shapeless, showery, slender, slenderish,
   slight, slight-made, slim, slimmish, slinky, small, smoggy, soupy,
   streaming, subtle, svelte, sylphlike, tenuous, thin, thin-bodied,
   thin-set, thin-spun, thinnish, threadlike, transcendent, uncertain,
   unclear, undefined, unintelligible, unordered, unorganized,
   unplain, unrecognizable, vague, wasp-waisted, watered,
   watered-down, watery, weak, willowy, wiredrawn, wispy