opacity

noun

opac·​i·​ty ō-ˈpa-sə-tē How to pronounce opacity (audio)
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)

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
For leaders, this offers a powerful mindset shift: failure isn’t the enemy—opacity is. Alain Hunkins, Forbes.com, 21 May 2025 Tarte’s Maracuja Juicy Lip Tattoo is a perfect example of these hybrid gloss stains that are not only made to be applied and forgotten about, but also provide you with a lot of options on finish, opacity, and lip shape. Sophia Panych, Allure, 20 May 2025 Holos addresses the common issue of ingredient opacity (where brands may not fully understand what’s in their products due to relying on third-party manufacturers) by keeping formulation in-house. Xandra Harbet, USA Today, 26 Apr. 2025 The latter thrive on volatility, opacity, and lack of accountability. John W. Dean, MSNBC Newsweek, 7 Apr. 2025 See All Example Sentences for opacity

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

Time Traveler
The first known use of opacity was in 1575

Browse Nearby Words

Cite this Entry

“Opacity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/opacity. Accessed 29 May. 2025.

Kids Definition

opacity

noun
opac·​i·​ty ō-ˈpas-ət-ē How to pronounce opacity (audio)
plural opacities
: the quality or state of being opaque

Medical Definition

opacity

noun
opac·​i·​ty ō-ˈpas-ət-ē How to pronounce opacity (audio)
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)

More from Merriam-Webster on opacity

Last Updated: - Updated example sentences
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