OPAQUE
opaque
(adjective) not transmitting or reflecting light or radiant energy; impenetrable to sight; “opaque windows of the jail”; “opaque to X-rays”
opaque, unintelligible
(adjective) hard or impossible to understand
Source: WordNet® 3.1
Etymology
Adjective
opaque (comparative more opaque or opaquer, superlative most opaque or opaquest) (see usage notes)
Neither reflecting nor emitting light.
Allowing little light to pass through, not translucent or transparent.
(figuratively) Unclear, unintelligible, hard to get or explain the meaning of
(figuratively) Obtuse, stupid.
(computing) Describes a type for which higher-level callers have no knowledge of data values or their representations; all operations are carried out by the type's defined abstract operators.
Usage notes
• The comparative opaquer and superlative opaquest, though formed following valid rules for English, are much less common than more opaque and most opaque and seem to occur more frequently in poetry.
• Most opaque has been more common than opaquest for at least two centuries and 50 to 100 times more common in the last two decades, according to this Google Ngram comparison.
Antonyms
• (physically): see-through, translucent, transparent
• (figuratively): clear, obvious, bright, brilliant
Noun
opaque (plural opaques)
(obsolete, poetic) An area of darkness; a place or region with no light.
Something which is opaque rather than translucent.
Verb
opaque (third-person singular simple present opaques, present participle opaquing, simple past and past participle opaqued)
(transitive) To make, render (more) opaque.
Synonyms
• blur
• cloud
Source: Wiktionary
O*paque", a. Etym: [F., fr. L. opacus. Cf. Opacous.]
1. Impervious to the rays of light; not transparent; as, an opaque
substance.
2. Obscure; not clear; unintelligible. [Colloq.]
O*paque", n.
Definition: That which is opaque; opacity. Young.
Source: Webster’s Unabridged Dictionary 1913 Edition