opacity

noun
opac·​i·​ty | \ ō-ˈpa-sə-tē \
plural opacities

Definition of opacity

1a : 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)

Keep scrolling for more

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

Once the sky’s opacity reaches a low enough level, the agency will decide whether to begin the 45-day listening period. John Wenz, Popular Mechanics, "Opportunity May Not Come Back Until January. NASA May Not Give It That Long.," 1 Sep. 2018 Central bankers a generation ago prided themselves on silence and opacity. Nick Timiraos, WSJ, "Fed Weighs Wait-and-See Approach on Future Rate Increases," 6 Dec. 2018 The 45-day timeline, which has not yet begun and will begin when opacity levels drop low enough, was decided based on input from across the Opportunity team. John Wenz, Popular Mechanics, "Opportunity May Not Come Back Until January. NASA May Not Give It That Long.," 1 Sep. 2018 Omnicom’s unrelenting focus on more traditional creative work and the opacity of its accounting could yet become problems. Stephen Wilmot, WSJ, "Madison Avenue Needs to Watch Its Back," 13 Nov. 2018 Facial recognition technology accelerates such judgments, makes them at a larger scale, and does so with a greater level of opacity. Diana Budds, Curbed, "Facial recognition is becoming one of the 21st century’s biggest public space issues," 19 Oct. 2018 When the plan was announced, some scientists affiliated with the mission expressed concern that pegging this active-listening period to the atmospheric opacity would start the clock on Opportunity too soon. Meghan Bartels, Space.com, "NASA Starts 45-Day Clock to Contact Mars Rover Opportunity as Dust Storm Wanes," 12 Sep. 2018 And that just speaks to maybe some of the financial opacity that’s inherent in looking at income statements and balance sheets and things like that. Recode Staff, Recode, "Why ‘Star Wars’ is like a social network, and other insights from Eugene Wei on Recode Media," 13 July 2018 The technicians visually assessed the overall opacity of the toilet paper; the thinner the product, sometimes the less the performance. Kathleen Huddy, Good Housekeeping, "Notes from the Lab: Toilet Paper Testing," 8 Sep. 2011

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'opacity.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of opacity

1575, in the meaning defined at sense 1a

History and Etymology for opacity

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

Keep scrolling for more

Learn More about opacity

Dictionary Entries near opacity

opacate

opacifier

opacimeter

opacity

opacous

opah

opakapaka

Statistics for opacity

Last Updated

5 Jan 2019

Look-up Popularity

Time Traveler for opacity

The first known use of opacity was in 1575

See more words from the same year

Keep scrolling for more

More Definitions for opacity

opacity

noun

English Language Learners Definition of opacity

: 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

opacity

noun
opac·​i·​ty | \ ō-ˈpas-ət-ē \
plural opacities

Medical Definition of opacity

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)

Keep scrolling for more

Comments on opacity

What made you want to look up opacity? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

important, real, or meaningful

Get Word of the Day daily email!

Test Your Vocabulary

Homophone Quiz

  • three-bears-two-of-them-look-like-theyre-whispering-to-a-third-bear-who-looks-chuffed-to-be-the-center-of-attention
  • In order to judge how people felt, the senator's office hired a firm to take a ______.
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!