acuity (noun) - sharpness or keenness, particularly in relation to perception or thought [uh-kyoo-i-tee]
BREAKDOWN: ACU- (sharp) + -ITY (quality)
acute means sharp; severe in effect; intense; extremely great or serious; critical
acute, when describing a disease, means brief and severe, as opposed to chronic, which means developing slowly, lingering long, or recurring frequently
acute, when describing an angle, means less than 90 degrees, as opposed to obtuse, which means greater than 90 degrees
See also: acerbic, acrimonious
“Mountains are cathedrals: grand and pure, the houses of my religion. I go to them as humans go to worship...From their lofty summits, I view my past, dream of the future, and with unusual acuity I am allowed to experience the present moment. My strength renewed, my vision cleared, in the mountains I celebrate creation. On each journey I am reborn.” —Anatoli Boukreev