a. Reacting readily to stimuli or impressions; sensitive: His hearing was unusually acute.
b. Keenly perceptive or discerning: an acute critic of music; a critic with acute judgment. See Synonyms at sharp.
2. Extremely sharp or severe; intense: acute pain; acute pleasure.
3. Of great importance or consequence; critical: an acute shortage of funds.
a. Having a rapid onset and following a short but severe course: an acute disease.
b. Afflicted by a disease exhibiting a rapid onset followed by a short, severe course: acute patients.
5. High in pitch; shrill: an acute scream.
a. Narrowly pointed; sharp: an acute leaf.
b. Having an acute angle: an acute triangle.
[Latin acūtus, past participle of acuere, to sharpen, from acus, needle; see ak- in the Appendix of Indo-European roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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