sharp / shärp/ • adj. 1. (of an object) having an edge or point that is able to cut or pierce something: cut the cake with a very sharp knife keep tools sharp. ∎  producing a sudden, piercing physical sensation or effect: I suddenly felt a sharp pain in my back. ∎  (of a food, taste, or smell) acidic and intense: sharp goats' milk cheese. ∎  (of a sound) sudden and penetrating: there was a sharp crack of thunder. ∎  (of words or a speaker) intended or intending to criticize or hurt: she feared his sharp tongue. ∎  (of an emotion or experience) felt acutely or intensely; painful: her sharp disappointment was tinged with embarrassment.2. tapering to a point or edge: a sharp pencil her face was thin and her nose sharp. ∎  distinct in outline or detail; clearly defined: the job was a sharp contrast from her past life | the scene was as sharp and clear in his mind as a film. ∎ inf. (of clothes or their wearer) neat and stylish: they were greeted by a young man in a sharp suit.3. (of an action or change) sudden and marked: there was a sharp increase in interest rates he heard her sharp intake of breath. ∎  (of a bend, angle, or turn) making a sudden change of direction: a sharp turn in the river. ∎  having or showing speed of perception, comprehension, or response: her sharp eyes missed nothing | his old mind was not so sharp as it once was | he had a sharp sense of humor. ∎  quick to take advantage, esp. in an unscrupulous or dishonest way: Paul's a sharp operator.4. (of musical sound) above true or normal pitch. ∎  [in comb.] (of a note) a semitone higher than a specified note: the song sits on E and F-sharp | the quartet in C-sharp minor. ∎  (of a key) having a sharp or sharps in the key signature: recorder players are most comfortable in sharp keys.• adv. 1. precisely (used after an expression of time): the meeting starts at 7:30 sharp.2. in a sudden or abrupt way: the creek bent sharp left he was brought up sharp by Helen's voice.3. above the true or normal pitch of musical sound: he heard him playing a little sharp on the high notes.• n. 1. a musical note raised a semitone above natural pitch. ∎  the sign (♯) indicating this.2. a long, sharply pointed sewing needle. ∎  (usu. sharps) a thing with a sharp edge or point, such as a hypodermic needle, a blade, or a fragment of glass: the safe disposal of sharps and clinical waste.3. inf. a swindler or cheat. See also card sharp.• v. [tr.] 1. [usu. as adj.] (sharped) Mus. raise the pitch of (a note).2. archaic cheat or swindle (someone), esp. at cards: the fellow is drunk, let's sharp him.PHRASES: sharp as a tack extremely clever or astute.DERIVATIVES: sharp·ly adv.sharp·ness n.

sharp having a keen edge or point; keen, acute; severe, harsh; pungent OE.; shrill XIV; (mus.) XVI; sb. uses date from XIV. OE. sċ(e)arp = OS. skarp (Du. scherp), OHG. skarf, scarpf(G. scharf), ON. skarpr :- Gmc. *skarpaz; cf. OE. sċearpe scarification, sċearpian scarify, OHG. scurfen (G. schürfen scratch), and SCRAPE.
Hence sharpen XV. superseding (dial.) sharp, OE. *sċierpan, sċerpan; see -EN5. sharper cheat, swindler. XVII. See -ER1; cf. sharp vb. swindle (XVII). sharply (-LY2), sharpness OE.

sharp.
1. As noun, the sign (♯) which, placed by a note, raises its pitch by a semitone. A sharp in the key signature affects all notes on corresponding degree of scale. See inflection of notes. (In Amer. usage a note is ‘sharped'; in Eng. ‘sharpened’.)

2. As adjective, describes singing or playing which departs from correct intonation upwards (opposite of flat, downwards).

sharp In musical notation, an accidental sign placed before a note or immediately after the clef to indicate that the note it refers to should be sounded a semitone higher. It is designated by the sign ^#.