English noun: opacity | 
| 1.  | opacity (phenomenon) the phenomenon of not permitting the passage of electromagnetic radiation | 
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  | Broader (hypernym) | physical phenomenon | 
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  | Narrower (hyponym) | optical opacity, radio-opacity, radiopacity | 
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  | Antonyms | transparence, transparency | 
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| 2.  | opacity (attribute) incomprehensibility resulting from obscurity of meaning | 
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  | Synonyms | opaqueness | 
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  | Broader (hypernym) | incomprehensibility | 
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| 3.  | opacity (attribute) the quality of being opaque to a degree; the degree to which something reduces the passage of light | 
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  | Synonyms | opaqueness | 
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  | Broader (hypernym) | quality | 
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  | Narrower (hyponym) | blurriness, cloudiness, fogginess, fuzziness, indistinctness, muddiness, murkiness, softness | 
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  | Attribute | opaque | 
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  | Antonyms | uncloudedness, clarity, clearness | 
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