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sharp (shärp)
adj. sharp·er, sharp·est
1. Having a thin edge or a fine point suitable for or capable of cutting or piercing.
a. Having clear form and detail: a sharp photographic image.
b. Terminating in an edge or a point: sharp angular cliffs; a sharp nose.
c. Clearly and distinctly set forth: sharp contrasts in behavior.
3. Abrupt or acute: a sharp drop; a sharp turn.
a. Intellectually penetrating; astute: was sharp in his analysis of the problem.
b. Marked by keenness and accuracy of perception: sharp hearing.
5. Crafty or deceitful, as in business dealings: sharp selling practices.
6. Vigilant; alert: kept a sharp lookout for shoplifters.
a. Briskly or keenly cold and cutting: a sharp wind.
b. Harsh or biting in tone or character: sharp criticism.
8. Fierce or impetuous; violent: a sharp temper; a sharp assault.
9. Intense; severe: a sharp pain.
a. Sudden and shrill: a sharp whistle.
b. Sudden and brilliant or dazzling: a sharp flash of lightning.
11. Strongly affecting the senses of smell and taste: a sharp pungent odor; a sharp cheese.
12. Composed of hard angular particles: sharp sand.
13. Music
a. Raised in pitch by a semitone.
b. Being above the proper pitch.
c. Having the key signature in sharps.
14. Informal Attractive or stylish: a sharp jacket.
1. In a sharp manner: hit me sharp on the brow.
2. Punctually; exactly: at three o'clock sharp.
3. Music Above the true or proper pitch.
1. Music
a. A sign () used to indicate that a note is to be raised by a semitone.
b. A note that is raised a semitone.
a. A slender sewing needle with a very fine point.
b. A hypodermic needle: a canister for disposing of used sharps.
3. Informal
a. An expert.
b. A shrewd cheater; a sharper.
v. sharped, sharp·ing, sharps
To raise in pitch by a semitone.
To play or sing above the proper pitch.

[Middle English, from Old English scearp; see sker-1 in the Appendix of Indo-European roots.]

sharply adv.
sharpness n.

Synonyms: sharp, keen1, acute
These adjectives all apply literally to fine edges, points, or tips. Figuratively they indicate mental alertness and clarity of comprehension. Sharp suggests quickness and astuteness: "a young man of sharp and active intellect" (John Henry Newman).
Keen implies clear-headedness and acuity: a journalist with a keen mind and quick wits.
Acute suggests penetrating perception or discernment: an acute observer of national politics. See Also Synonyms at fashionable.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
Sharp (shärp), Phillip Allen Born 1944.
American biochemist who shared a 1993 Nobel Prize for discovering that some genes contain sequences, known as introns, that do not function as codes for the formation of a protein.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.