1. (noun)key metaldevice shaped in such a way that when it is inserted into the appropriate lock the lock's mechanism can be rotated
2. (noun)key something crucial for explaining "the key to development is economic integration"
3. (noun)key pitch of the voice "he spoke in a low key"
4. (noun)key, tonality any of 24 major or minor diatonic scales that provide the tonal framework for a piece of music
5. (noun)key a kilogram of a narcoticdrug "they were carrying two keys of heroin"
6. (noun)samara, key fruit, key a winged often one-seed indehiscent fruit as of the ash or elm or maple
7. (noun)Key, Francis Scott Key United States lawyer and poet who wrote a poem after witnessing the Britishattack on Baltimore during the War of 1812; the poem was later set to music and entitled `The Star-Spangled Banner' (1779-1843)
9. (noun)key, paint (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"
10. (noun)key a list of answers to a test "some students had stolen the key to the final exam"
11. (noun)key a list of words or phrases that explain symbols or abbreviations
15. (adj)key a lever (as in a keyboard) that actuates a mechanism when depressed
16. (verb)cardinal, central, fundamental, key, primal serving as an essentialcomponent "a cardinal rule"; "the central cause of the problem"; "an example that was fundamental to the argument"; "computers are fundamental to modern industrial structure"
17. (verb)identify, discover, key, key out, distinguish, describe, name identify as in botany or biology, for example
18. (verb)key provide with a key "We were keyed after the locks were changed in the building"
19. (verb)key vandalize a car by scratching the sides with a key "His new Mercedes was keyed last night in the parking lot"
Definition of 'KEY' 
