[1] : The Collaborative International Dictionary of English v.0.48

opaque \opaque"\, a. f., fr. l. opacus. cf. opacous.
   1913 webster
   1. impervious to the rays of light; not transparent; as, an
      opaque substance.
      1913 webster

   2. obscure; not clear; unintelligible. colloq.
      1913 webster
see also:
opacous 

[2] : The Collaborative International Dictionary of English v.0.48

opaque \opaque"\, n.
   that which is opaque; opacity. --young.
   1913 webster

[3] : WordNet (r) 2.0

opaque
     adj 1: not clear; not transmitting or reflecting light or radiant
            energy; "opaque windows of the jail"; "opaque to
            x-rays" ant: clear
     2: not clearly understood or expressed syn: unintelligible
see also:
clear unintelligible 

[4] : Moby Thesaurus II by Grady Ward, 1.0

97 moby thesaurus words for "opaque":
   boeotian, abstruse, adiaphanous, ambiguous, amorphous,
   amphibological, arcane, asinine, backward, baffling, becloud,
   beef-brained, beef-witted, black, blind, blockish, blurred, blurry,
   bovine, chumpish, clear as mud, cloddish, cloud, clouded, cloudy,
   cowish, crass, cryptic, dark, darken, dense, dim, doltish, dull,
   dull-witted, dullard, dumb, duncical, duncish, dunderheaded,
   elusive, enigmatic, equivocal, fat, foggy, fuzzy, gross, grumly,
   hazy, impenetrable, impermeable, impervious to light, indefinite,
   indeterminate, indistinct, ineducable, intransparent, klutzy,
   lumpish, misty, muddy, murky, mysterious, mystifying, nebulous,
   nubilous, oafish, obfuscated, obscure, obscured, obtuse,
   perplexing, puzzling, recondite, roiled, roily, shadowy, shapeless,
   slow, smoky, sottish, stolid, stupid, tenebrous, thick,
   thickheaded, transcendent, turbid, uncertain, unclear,
   unfathomable, unintelligent, unintelligible, unplain, unteachable,
   vague, wrongheaded

Opaque >> O Words
Opaque, definition of term: Opaque
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