opacity

noun opac·i·ty \ō-ˈpa-sə-tē\

: the quality of a material that does not allow light to pass through it : the quality of being opaque

: the quality of being difficult to understand or explain

plural opac·i·ties

Full Definition of OPACITY

a : obscurity of sense : unintelligibleness

b : the quality or state of being mentally obtuse : dullness

: the quality or state of a body that makes it impervious to the rays of light; broadly : the relative capacity of matter to obstruct the transmission of radiant energy

: an opaque spot in a normally transparent structure (as the lens of the eye)

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Origin of OPACITY

Middle French opacité shadiness, from Latin opacitat-, opacitas, from opacus shaded, dark

First Known Use: 1560

Related to OPACITY

Synonyms: ambiguity, ambiguousness, darkness, equivocalness, equivocation, inscrutability, inscrutableness, murkiness, mysteriousness, nebulosity, nebulousness, obliqueness, obliquity, obscurity, opaqueness

Antonyms: clarity, clearness, obviousness, plainness

Rhymes with OPACITY

audacity, capacity, edacity, fugacity, loquacity, mendacity, predacity, pugnacity, rapacity, sagacity, sequacity, tenacity, veracity, vivacity, voracity

Medical Dictionary

opacity

noun opac·i·ty \ō-ˈpas-ət-ē\

plural opac·i·ties

Medical Definition of OPACITY

: the quality or state of a body that makes it impervious to the rays of light; broadly : the relative capacity of matter to obstruct by absorption or reflection the transmission of radiant energy (as X-rays, infrared radiation, or sound)

: an opaque spot in a normally transparent structure (as the lens of the eye)