opacity

noun

opac·​i·​ty ō-ˈpa-sə-tē 

plural opacities

1

a

: obscurity of sense : unintelligibility

b

: the quality or state of being mentally obtuse : dullness

2

: 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

3

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

Synonyms

• ambiguity
• ambiguousness
• darkness
• equivocalness
• equivocation
• inscrutability
• inscrutableness
• murkiness
• mysteriousness
• nebulosity
• nebulousness
• obliqueness
• obliquity
• obscurity
• opaqueness

Examples of opacity in a Sentence

the opacity of the glass

Critics have noted the opacity of her writing style.

Recent Examples on the Web

Within the technology supply chain, this opacity can cause problems, especially when global trends like ESG mandates, re-globalization and geopolitical tensions demand closer collaboration with suppliers. —Koray Köse, Forbes, 11 Dec. 2024

My non-Asian friends were interested in non-Asian things—playing guitar, professional wrestling, R.V. trips—that meant nothing to me; the mutual opacity of our cultures seemed normal. —Joshua Rothman, The New Yorker, 17 Sep. 2024

The high degree of leverage, opacity obscuring the mechanics of a giant family conglomerate and perceived closeness to the political elite are all there. —William Pesek, Forbes, 25 Nov. 2024

Gradated markings ensure that the two lenses both get set to the same opacity. —Ben Coxworth, New Atlas, 5 Nov. 2024

Word History

Etymology

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

First Known Use

1575, in the meaning defined at sense 1a

Kids Definition

opacity

noun

opac·​i·​ty ō-ˈpas-ət-ē 

plural opacities

: the quality or state of being opaque

Medical Definition

opacity

noun

opac·​i·​ty ō-ˈpas-ət-ē 

plural opacities

1

: 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)

2

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