definition of
acuity

[1] #1 acuity n. [visual acuity, sharp-sightedness] sharpness of vision; the visual ability to resolve fine detail (usually measured by a Snellen chart). wn

[2] #2 acuity n. [acuteness, sharpness, keenness] a quick and penetrating intelligence; "he argued with great acuteness"; "I admired the keenness of his mind". wn