acuity

noun

acu·​i·​ty ə-ˈkyü-ə-tē How to pronounce acuity (audio)
a-
plural acuities
: keenness of perception
hearing acuity
mental acuity

Did you know?

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
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.
The charismatic, 46-year-old Moore would be a welcome respite for a party still bedeviled by Biden’s legacy-defining decision to seek reelection despite mental and physical acuity problems. Mabinty Quarshie, The Washington Examiner, 28 June 2025 Italian law dictates that citizens over 80 must renew their license every two years and complete a medical examination that tests mental acuity. Rachel Raposas, People.com, 19 June 2025 Higher acuity patients often require more specialized staff. Kunal Khashu, Forbes.com, 18 June 2025 Oversight in cognitive decline ‘cover-up’ investigation | RISING Niall Stanage and Amber Duke discuss four former Biden aides agreeing to testify to the house oversight committee about the former President’s health and mental acuity. The Hill, 12 June 2025 See All Example Sentences for acuity

Word History

Etymology

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

First Known Use

circa 1549, in the meaning defined above

Time Traveler
The first known use of acuity was circa 1549

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Cite this Entry

“Acuity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acuity. Accessed 11 Jul. 2025.

Kids Definition

acuity

noun
acu·​ity ə-ˈkyü-ət-ē How to pronounce acuity (audio)
: sharpness of perception

Medical Definition

acuity

noun
acu·​ity ə-ˈkyü-ət-ē How to pronounce acuity (audio)
plural acuities
: keenness of sense perception
acuity of hearing
see visual acuity

More from Merriam-Webster on acuity

Last Updated: - Updated example sentences
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