Opacity

n. opaqueness; degree to which something is opaque; obscurity; fuzziness; amount of area on a film that absorbs light (Photography); stupidity

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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Opacity /opac·i·ty/ 1. the condition of being opaque. 2. an opaque area. o·pac·i·ty n. 1. The quality or state of being opaque. 2. [more]Opacity - Community and Resources

Noun
1. the phenomenon of not permitting the passage of electromagnetic radiation
(antonym) transparency, transparence
(hypernym) physical phenomenon
(hyponym) optical opacity
2. incomprehensibility resulting from obscurity of meaning
(synonym) opaqueness
(hypernym) incomprehensibility
3. the quality of being opaque to a degree; the degree to which something reduces the passage of light
(synonym) opaqueness
(antonym) clearness, clarity, uncloudedness
(hypernym) quality
(hyponym) cloudiness, murkiness, muddiness
(attribute) opaque

(n.)
The state of being opaque; the quality of a body which renders it impervious to the rays of light; want of transparency; opaqueness.
  

(n.)
Obscurity; want of clearness.