opaque

adj. not transparent, entirely obstructing the passage of light; obstructing the passage of radiation (Physics); frosted (about glass); dull; stupid

n. that which entirely obstructs the passage of light; fluid for photographic negatives

Opacity or opaque refers to something difficult to see through or perceive. It can refer to:Opacity (optics), Degree to which light is blocked.Opaque context, a linguistic context in which it is not possible to substitute co-referential terms while guaranteeing the preservation of truth values.Opaque data, in computer programming, data that can only be manipulated through an external interface
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Adjective
1. not clear; not transmitting or reflecting light or radiant energy; "opaque windows of the jail"; "opaque to X-rays"
(antonym) clear
(similar) cloudy, muddy, mirky, murky, turbid
(see-also) unclear
(attribute) opacity, opaqueness
2. not clearly understood or expressed
(synonym) unintelligible
(similar) incomprehensible, uncomprehensible

adj. opaque, not transparent; entirely obstructing the passage of light; obstructing the passage of radiation (Physics)

v. darken, make dark; dim; grow dark