—n. 1. a small metal instrument specially cut to fit into a lock and move its bolt.
2. any of various devices resembling or functioning as a key: the key of a clock. 3. See key card. 4. something that affords a means of access: the key to happiness. 5. something that secures or controls entrance to a place: Gibraltar is the key to the Mediterranean. 6. something that affords a means of clarifying a problem.
7. a book, pamphlet, or other text containing the solutions or translations of material given elsewhere, as testing exercises.
8. a systematic explanation of abbreviations, symbols, etc., used in a dictionary, map, etc.: pronunciation key. Cf. legend (def. 4).
9. the system, method, pattern, etc., used to decode or decipher a cryptogram, as a code book, machine setting, or key word.
10. one of a set of marked parts, designated areas, or levers pressed in operating a typewriter, computer terminal, calculator, etc.
11. a manually operated lever for opening and closing an electric circuit, used to produce signals in telegraphy.
12. Music. a. (in a keyboard instrument) one of the levers that when depressed by the performer sets in motion the playing mechanism.
b. (on a woodwind instrument) a metal lever that opens and closes a vent.
c. the relationship perceived between all tones in a given unit of music and a single tone or a keynote; tonality.
d. the principal tonality of a composition: a symphony in the key of C minor. e. the keynote or tonic of a scale.
13. tone or pitch, as of voice: to speak in a high key. 14. mood or characteristic style, as of expression or thought: He writes in a melancholy key. 15. degree of intensity, as of feeling or action.
16. a pin, bolt, wedge, or other piece inserted in a hole or space to lock or hold parts of a mechanism or structure together; a cotter.
17. a small piece of steel fitting into matching slots of a hub of a wheel or the like and the shaft on which the wheel is mounted so that torque is transmitted from one to the other.
18. a contrivance for grasping and turning a bolt, nut, etc.
19. Computers.a field or group of characters within a record that identifies the record, establishing its position among sorted records, and/or provides information about its contents.
20. (in a series of advertisements or announcements soliciting replies) a unique code inserted for each medium used, to determine the relative effectiveness of the media.
21. Elect. a. a device for opening and closing electrical contacts.
b. a hand-operated switching device ordinarily formed of concealed spring contacts with an exposed handle or push button, capable of switching one or more parts of a circuit.
22. Biol.a systematic tabular classification of the significant characteristics of the members of a group of organisms to facilitate identification and comparison.
23. Masonry.a keystone.
24. Archit.(in a ribbed vault) a stone, as a boss, at the intersection of two or more ribs.
25. Masonry,Carpentry.a wedge, as for tightening a joint or splitting a stone or timber.
26. Carpentry.a small piece of wood set into a timber across the grain to prevent warping.
27. Building Trades.any grooving or roughness applied to a surface to improve its bond with another surface.
28. Basketball.keyhole (def. 2).
29. Photog.the dominant tonal value of a picture, a high-key picture having light tonal values and minimal contrast and a low-key picture being generally dark with minimal contrast.
30. Painting.the tonal value and intensity of a color or range of colors: Rembrandt's colors are characterized by their low key. 31. Bot.a samara.
32. (cap.) a member of the House of Keys.
33. keys,spiritual authority.
34. power of the keys, the authority of a pope in ecclesiastical matters, vested in him as successor of St. Peter.
—adj. chief; major; important; essential; fundamental; pivotal: a key person in the company; key industries.
—v.t. 1. to regulate or adjust (actions, thoughts, speech, etc.) to a particular state or activity; bring into conformity: to key one's speech to the intellectual level of the audience. 2. Music.to regulate the key or pitch of.
3. Painting. a. to paint (a picture) in a given key.
b. to adjust the colors in (a painting) to a particular hue: He keyed the painting to brown. 4. to fasten, secure, or adjust with a key, wedge, or the like, as parts of a mechanism.
5. to provide with a key.
6. (in the layout of newspapers, magazines, etc.) to identify, through signs or symbols, the positions of illustrations or pieces of copy in a dummy.
7. to lock with or as if with a key.
8. Masonry.to provide (an arch or vault) with a keystone.
9. Computers.keyboard (def. 4).
—v.i. 1. to use a key.
2. Computers.keyboard (def. 4).
3. key in,Computers.keyboard (def. 4).
4. key on, a. Football.to watch the position and movements of an opponent in order to anticipate a play: The defensive backs keyed on the star receiver. b. Also,key in on.to single out as of prime importance or interest; be intent on or obsessed with: a company that is keyed in on growth. 5. key up, a. to bring to a particular degree of intensity of feeling, excitement, energy, nervousness, agitation, etc.: keyed up over the impending test. b. to raise (a piece of masonry) by the insertion of a wedge or wedges.
c. to raise (the haunches of an arch) by the insertion of a voussoir.
Pronunciation: (kē),[key] —n., —pl.keys. a reef or low island; cay.
Pronunciation: (kē),[key] —n., —pl.keys.Slang. a kilogram of marijuana or a narcotic drug.
Pronunciation: (kē),[key] —n. Francis Scott, 1780–1843, U.S. lawyer: author of The Star-Spangled Banner.