1: 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" [syn: cardinal, central, fundamental, primal]
2: effective; producing a desired effect; "the operative word" [syn: operative]
1: metal device shaped in such a way that when it is inserted into the appropriate lock the lock's mechanism can be rotated
2: something crucial for explaining; "the key to development is economic integration"
3: pitch of the voice; "he spoke in a low key"
4: any of 24 major or minor diatonic scales that provide the tonal framework for a piece of music [syn: tonality] [ant: atonality]
5: a kilogram of a narcotic drug; "they were carrying two keys of heroin"
6: a winged often one-seed indehiscent fruit as of the ash or elm or maple [syn: samara, key fruit]
7: 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) [syn: Francis Scott Key]
8: a coral reef off the southern coast of Florida [syn: cay, Florida keys]
9: (basketball) a space (including the foul line) in front of the basket at each end of a basketball court; usually painted a different color from the rest of the court; "he hit a jump shot from the top of the key"; "he dominates play in the paint" [syn: paint]
10: a list of answers to a test; "some students had stolen the key to the final exam"
11: a list of words or phrases that explain symbols or abbreviations
12: a generic term for any device whose possession entitles the holder to a means of access; "a safe-deposit box usually requires two keys to open it"
13: mechanical device used to wind another device that is driven by a spring (as a clock) [syn: winder]
14: the central building block at the top of an arch or vault [syn: keystone, headstone]
15: a lever that actuates a mechanism when depressed
1: identify as in botany or biology, for example [syn: identify, discover, key out, distinguish, describe, name]
2: provide with a key; "We were keyed after the locks were changed in the building"
3: vandalize a car by scratching the sides with a key; "His new Mercedes was keyed last night in the parking lot"
4: regulate the musical pitch of
5: harmonize with or adjust to; "key one's actions to the voters' prevailing attitude"
Adjacent words: kettle | kettle hole | kettle of fish | kettledrum | kettleful | Ketubim | keurboom | key | key fruit | key lime | key out | key palm | key pattern | key ring | key signature | Key West