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 of acuity

• 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

That’s evident in both her mental acuity as well as her physical agility, demonstrated by her ease in climbing several flights of stairs to enter her spacious apartment. — Marshall Shaffer, IndieWire, 9 Sep. 2026

In his exquisitely layered seventh feature, Possible Love (Ga-neung-han sa-rang), Lee Chang-dong’s humanistic observational skills remain at their peak, the acuity of his insights into emotional lives and social conditions unparalleled. — David Rooney, HollywoodReporter, 6 Sep. 2026

The best of Ascherson’s writing manages to capture both large themes and sensory detail with passion and acuity. — Isaac Chotiner, New Yorker, 3 Sep. 2026

This is one of risk’s most obvious gifts, the chance to experience that rare, thin-slicing acuity where each separate millisecond stands out like an image etched in stone. — Brian Laidlaw, Longreads, 1 Sep. 2026

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

• ambiguity
• contiguity
• continuity
• incongruity
• ingenuity
• perpetuity
• perspicuity
• promiscuity
• superfluity
• annuity
• circuity
• congruity

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

1

: keenness of sense perception

acuity of hearing

see visual acuity

2

: the severity of a patient's medical condition

… a scale of 1–5 where 5 represents a high level of care intensity and patient acuity.

—Maame Yaa A.B. Yiadom et al., Academic Emergency Medicine