acu·​i·​ty | \ ə-ˈkyü-ə-tē How to pronounce acuity (audio) , a- \
plural acuities

Definition of acuity

: keenness of perception hearing acuity mental acuity

Do you have acuity or sensitivity?

Acuity is nearly synonymous with at least one sense of sensitivity, yet, as is so often the case with closely-related words, there are subtle differences worth observing before you substitute one of these words for the other. Acuity does refer to a form of sensitivity, but it is most often applied to the perceptual senses (as in “visual acuity” or “auditory acuity”). It is also frequently used in reference to the intellect (as in “mental acuity”). Sensitivity has a broader range of meanings than acuity does, including “the capacity of being easily hurt.” It may be used of inanimate objects such as radios (“the sensitivity of the instruments was carefully calibrated”), a context in which acuity is unusual.

Examples of acuity in a Sentence

a worrisome deterioration in the acuity of his hearing over the years
Recent Examples on the Web Although Feinstein still seems capable of doing her job, her mental acuity has visibly declined in recent years. Los Angeles Times, 27 Apr. 2022 The directors witnessed the effects of Willis losing his mental acuity, which often resulted in the actor being unable to remember his dialogue. Zack Sharf, Variety, 31 Mar. 2022 On everything from Covid-19 mitigation measures (or a lack thereof) to critical race theory to the mental acuity of President Joe Biden, DeSantis has used Fox as both a guidepost and an amplifier of where to stand on these issues. Chris Cillizza, CNN, 1 Apr. 2022 The Fox host shared statistics challenging the acuity of America's perception of reality, saying that America is being brainwashed by the Left. Jack Durschlag, Fox News, 30 Mar. 2022 The roboride was part of a scientific study to test whether goldfish had the mental acuity to navigate a terrestrial environment toward a target using a machine. Daniela Hernandez, WSJ, 6 Feb. 2022 HearID measures the hearing acuity of the listener and then produces a tone profile that boosts any frequencies that the listener’s ear might be struggling to hear. Mark Sparrow, Forbes, 7 Oct. 2021 Judge Glen once approved the termination of a guardianship of a young woman originally deemed to have the mental acuity of a 7-year-old. New York Times, 23 July 2021 Some described heart-wrenching scenes as the star grappled with his loss of mental acuity and an inability to remember his dialogue, according to The Times’ report. Nardine Saadstaff Writer, Los Angeles Times, 1 Apr. 2022 See More

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

First Known Use of acuity

circa 1549, in the meaning defined above

History and Etymology for acuity

Middle English acuite "sharpness, acridity," borrowed from Middle French acuité, borrowed from Medieval Latin acuitāt-, acuitās, from Latin acu-, stem of acuere "to sharpen" + -itāt-, -itās -ity — more at acute

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Time Traveler for acuity

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The first known use of acuity was circa 1549

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Last Updated

15 May 2022

Cite this Entry

“Acuity.” Dictionary, Merriam-Webster, Accessed 29 May. 2022.

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More Definitions for acuity


acu·​ity | \ ə-ˈkyü-ət-ē How to pronounce acuity (audio) \
plural acuities

Medical Definition of acuity

: keenness of sense perception acuity of hearing — see visual acuity

More from Merriam-Webster on acuity

Nglish: Translation of acuity for Spanish Speakers

Britannica English: Translation of acuity for Arabic Speakers


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