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

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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 Late March, when your acuity with business affairs is at a peak, could be the best time to address investments or to make a decision about a major purchase. Tribune Content Agency, oregonlive, "Horoscope for Oct. 17, 2019: Virgo, strike while the iron is hot; Capricorn, fast reflexes for the win," 17 Oct. 2019 Pianist Levit brings considerable intellectual acuity and technical aplomb to this music, which arrives in time for next year’s worldwide celebration of the composer’s 250th birthday. Howard Reich,, "Best classical albums of 2019: World premieres, historic revivals and enticingly eclectic music," 27 Nov. 2019 Even so, Pavlova’s novel A Double Life shook the Russian literary world when it was published in 1848, earning widespread praise for its revolutionary form and psychological acuity. Talya Zax, The Atlantic, "The 19th-Century Feminist Novel Pushed Out of the Russian Canon," 5 Nov. 2019 Castro also seemed to allude to speculation about the 76-year-old Biden's mental acuity during an exchange about health care. Fortune, "Highlights From the Third Democratic Debate," 12 Sep. 2019 At last week’s TED Women conference in Palm Springs, California, TED’s staff once again proved its acuity for scouring the internet for great interstitial videos. Anne Quito, Quartz at Work, "Energize your meetings with empowering videos like the ones used by TED," 10 Dec. 2019 The former vice-president has dominated the primary’s moderate lane despite his familiar shortcomings as a campaigner and more recent doubts about his mental acuity. The Economist, "Amy Klobuchar for sanity," 24 Oct. 2019 Blame your friend's acuity and the quality of your friendship. Carolyn Hax, oregonlive, "Carolyn Hax: Time to tell best friend about her husband’s groping attempts," 9 Oct. 2019 Doctors rely mostly on tests of mental acuity and interviews with the patient and family members. New York Times, "A Blood Test for Alzheimer’s? It’s Coming, Scientists Report," 1 Aug. 2019

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.

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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

Time Traveler

The first known use of acuity was circa 1549

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Statistics for acuity

Last Updated

15 Jan 2020

Cite this Entry

“Acuity.” The Dictionary, Merriam-Webster Inc., Accessed 17 January 2020.

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More Definitions for acuity


How to pronounce acuity (audio)

English Language Learners Definition of acuity

formal : the ability to see, hear, or understand something easily


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

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More from Merriam-Webster on acuity

Thesaurus: All synonyms and antonyms for acuity

Rhyming Dictionary: Words that rhyme with acuity

Nglish: Translation of acuity for Spanish Speakers

Britannica English: Translation of acuity for Arabic Speakers

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