The Collaborative International Dictionary of English v.0.48:

Cloud \Cloud\ (kloud), v. t. [imp. & p. p. Clouded; p. pr. &
   vb. n. Clouding.]
   1. To overspread or hide with a cloud or clouds; as, the sky
      is clouded.
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   2. To darken or obscure, as if by hiding or enveloping with a
      cloud; hence, to render gloomy or sullen.
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            One day too late, I fear me, noble lord,
            Hath clouded all thy happy days on earth. --Shak.
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            Be not disheartened, then, nor cloud those looks.
                                                  --Milton.
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            Nothing clouds men's minds and impairs their honesty
            like prejudice.                       --M. Arnold.
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   3. To blacken; to sully; to stain; to tarnish; to damage; --
      esp. used of reputation or character.
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            I would not be a stander-by to hear
            My sovereign mistress clouded so, without
            My present vengeance taken.           --Shak.
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   4. To mark with, or darken in, veins or sports; to variegate
      with colors; as, to cloud yarn.
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            And the nice conduct of a clouded cane. --Pope.
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WordNet (r) 3.0 (2006):

clouded
    adj 1: made troubled or apprehensive or distressed in
           appearance; "his face was clouded with unhappiness"
    2: filled or abounding with clouds [syn: cloud-covered,
       clouded, overcast, sunless]
    3: mentally disordered; "a mind clouded by sorrow"
    4: unclear in form or expression; "the blurred aims of the
       group"; "sometimes one understood clearly and sometimes the
       meaning was clouded"- H.G.Wells [syn: blurred, clouded]

Moby Thesaurus II by Grady Ward, 1.0:

129 Moby Thesaurus words for "clouded":
   Acheronian, Acherontic, Cimmerian, Stygian, abstruse, ambiguous,
   armored, beclouded, blind, buried, calico, cased, castellatus,
   ceiled, cirrose, cirrous, cloaked, close, cloud-flecked, cloudy,
   coated, concealed, coped, covered, covert, cowled, cumuliform,
   cumulous, curtained, dapple, dappled, dark, dark and gloomy, dirty,
   dubious, eclipsed, encapsulated, encapsuled, encased, enveloped,
   enwrapped, equivocal, filmed, floored, funereal, gloomful,
   glooming, gloomy, heavy, hid, hidden, hooded, housed, ill-lighted,
   ill-lit, in a cloud, in a fog, in eclipse, in purdah, in the wings,
   incommunicado, latent, lenticularis, loricate, loricated, lowering,
   mammatus, mantled, marbled, masked, motley, mottled, muffled,
   mysterious, nebulous, nimbose, nubilous, obfuscated, obscure,
   obscured, occult, occulted, open, overcast, overclouded, packaged,
   paved, pepper-and-salt, piebald, pied, pinto, problematic,
   recondite, roofed-in, screened, scummed, secluded, secluse, secret,
   sequestered, shady, sheathed, shelled, shielded, shrouded,
   skewbald, somber, sombrous, squally, stormy, stratiform, stratous,
   swathed, tented, thunderheaded, uncertain, unclear,
   under an eclipse, under cover, under house arrest, under wraps,
   underground, unknown, unsettled, veiled, walled, walled-in,
   wrapped, wrapped in clouds