Key word meaning and definition

[noun] metal device shaped in such a way that when it is inserted into the appropriate lock the lock's mechanism can be rotated
[noun] a lever that actuates a mechanism when depressed
[noun] mechanical device used to wind another device that is driven by a spring (as a clock)
[noun] pitch of the voice; "he spoke in a low key"
[noun] something crucial for explaining; "the key to development is economic integration"
[noun] a list of words or phrases that explain symbols or abbreviations
[noun] any of 24 major or minor diatonic scales that provide the tonal framework for a piece of music
[noun] a coral reef off the southern coast of Florida
[noun] United States lawyer and poet who wrote a poem after witnessing the British attack on Baltimore during the War of 1812; the poem was later set to music and entitled `The Star-Spangled Banner' (1779-1843)
[noun] one thousand grams; the basic unit of mass adopted under the System International d'Unites; "a kilogram is approximately 2.2 pounds"; "they were carrying two keys of heroin"
[adjective] serving as an essential component; "a cardinal rule"; "the central cause of the problem"; "an example that was fundamental to the argument"; "computers are fundamental to modern industrial structure"
[adjective] effective; producing a desired effect; "the operative word"
[verb] harmonize with or adjust to; "key one's actions to the voters' prevailing attitude"
[verb] regulate the musical pitch of
[verb] identify as in botany or biology, for example
[verb] vandalize a car by scratching the sides with a key"; "His new Mercedes was keyed last night in the parking lot"
[verb] provide with a key; "We were keyed after the locks were changed in the building"

\Key\ (k[=e]), n. [OE. keye, key, kay, AS. c[ae]g.] 1. An instrument by means of which the bolt of a lock is shot or drawn; usually, a removable metal instrument fitted to the mechanism of a particular lock and operated by turning in its place. 2. An instrument which is turned like a key in fastening or adjusting any mechanism; as, a watch key; a bed key, etc. 3. That part of an instrument or machine which serves as the means of operating it; as, a telegraph key; the keys of a pianoforte, or of a typewriter. 4. A position or condition which affords entrance, control, pr possession, etc.; as, the key of a line of defense; the key of a country; the key of a political situation. Hence, that which serves to unlock, open, discover, or solve something unknown or difficult; as, the key to a riddle; the key to a problem. Those who are accustomed to reason have got the true key of books. --Locke. Who keeps the keys of all the creeds. --Tennyson. 5. That part of a mechanism which serves to lock up, make fast, or adjust to position. 6. (Arch.)
(a) A piece of wood used as a wedge.
(b) The last board of a floor when laid down. 7. (Masonry)
(a) A keystone.
(b) That part of the plastering which is forced through between the laths and holds the rest in place. 8. (Mach.)
(a) A wedge to unite two or more pieces, or adjust their relative position; a cotter; a forelock. See Illusts. of {Cotter}, and {Gib}.
(b) A bar, pin or wedge, to secure a crank, pulley, coupling, etc., upon a shaft, and prevent relative turning; sometimes holding by friction alone, but more frequently by its resistance to shearing, being usually embedded partly in the shaft and partly in the crank, pulley, etc. 9. (Bot.) An indehiscent, one-seeded fruit furnished with a wing, as the fruit of the ash and maple; a samara; -- called also {key fruit}. 10. (Mus.)
(a) A family of tones whose regular members are called diatonic tones, and named key tone (or tonic) or one (or eight), mediant or three, dominant or five, subdominant or four, submediant or six, supertonic or two, and subtonic or seven. Chromatic tones are temporary members of a key, under such names as `` sharp four,'' ``flat seven,'' etc. Scales and tunes of every variety are made from the tones of a key.
(b) The fundamental tone of a movement to which its modulations are referred, and with which it generally begins and ends; keynote. Both warbling of one song, both in one key. --Shak. 11. Fig: The general pitch or tone of a sentence or utterance. You fall at once into a lower key. --Cowper. {Key bed}. Same as {Key seat}. {Key bolt}, a bolt which has a mortise near the end, and is secured by a cotter or wedge instead of a nut. {Key bugle}. See {Kent bugle}. {Key of a position} or {country.} (Mil.) See {Key}, 4. {Key seat} (Mach.), a bed or groove to receive a key which prevents one part from turning on the other. {Key way}, a channel for a key, in the hole of a piece which is keyed to a shaft; an internal key seat; -- called also {key seat}. {Key wrench} (Mach.), an adjustable wrench in which the movable jaw is made fast by a key. {Power of the keys} (Eccl.), the authority claimed by the ministry in some Christian churches to administer the discipline of the church, and to grant or withhold its privileges; -- so called from the declaration of Christ, ``I will give unto thee the keys of the kingdom of heaven.'' --Matt. xvi. 19.
\Key\, v. t. [imp. & p. p. {Keved}; p. pr. & vb. n. {Keying}.] To fasten or secure firmly; to fasten or tighten with keys or wedges. --Francis. {To key up}.
(a) (Arch.) To raise (the whole ring of an arch) off its centering, by driving in the keystone forcibly.
(b) (Mus.) To raise the pitch of.
(c) Hence, fig., to produce nervous tension in.
\Key\, n. (Teleg.) A metallic lever by which the circuit of the sending or transmitting part of a station equipment may be easily and rapidly opened and closed; any device for closing or opening an electric circuit.
\Key\, n. A simplified version or analysis which accompanies something as a clue to its explanation, a book or table containing the solutions to problems, ciphers, allegories, or the like, or a table or synopsis of conspicuous distinguishing characters of members of a taxonomic group.

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