acuity

noun

acu·​i·​ty ə-ˈkyü-ə-tē 

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.

Synonyms

• sensitivity
• sensitiveness

Examples of acuity in a Sentence

a worrisome deterioration in the acuity of his hearing over the years

Recent Examples on the Web

However, House Republicans have had success bringing high-profile officials before their committees for other investigations, particularly the inquiry into President Joe Biden’s mental acuity, and a Clinton appearance is not out of the question. —Lauren Green, The Washington Examiner, 7 Aug. 2025

Signs of aging in dogs include loss of vision, loss of hearing, weight gain, loss of energy, arthritis and other joint problems, loss of muscle tone, loss of teeth, loss of organ integrity (heart, liver, kidneys), loss of skin elasticity, loss of hair, loss of immunity, and loss of mental acuity. —Maria Azzurra Volpe, MSNBC Newsweek, 28 July 2025

Healthy paranoia, when embraced strategically, becomes an essential asset for leaders, providing more mental acuity, urgency, and vigilance against complacency, while demanding the durability necessary to excel consistently at the highest levels. —Julian Hayes Ii, Forbes.com, 20 July 2025

As the probe into Joe Biden’s mental acuity continues, the former president’s personal physician, Kevin O’Connor, DO, made an appearance this week in Washington, D.C., in front of the House Oversight Committee. —Angelica Stabile, FOXNews.com, 11 July 2025

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

Phrases Containing acuity

• hyper-acuity
• visual acuity

Rhymes for acuity

• annuity
• circuity
• congruity
• fatuity
• gratuity
• tenuity
• vacuity
• ambiguity
• contiguity
• continuity
• incongruity
• ingenuity

Kids Definition

acuity

noun

acu·​ity ə-ˈkyü-ət-ē 

: sharpness of perception

Medical Definition

acuity

noun

acu·​ity ə-ˈkyü-ət-ē 

plural acuities

: keenness of sense perception

acuity of hearing

see visual acuity