key meaning and definition

KEY noun

Definition of key (noun)

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
   • synonyms: tonality
   • antonym: atonalism
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
   • synonyms: key fruit, samara
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)
   • synonyms: Francis Scott Key
8. a coral reef off the southern coast of Florida
   • synonyms: cay, Florida key
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"
   • synonyms: 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)
    • synonyms: winder
14. the central building block at the top of an arch or vault
    • synonyms: headstone, keystone
15. a lever (as in a keyboard) that actuates a mechanism when depressed

KEY verb

Definition of key (verb)

1. identify as in botany or biology, for example
   • synonyms: describe, discover, distinguish, identify, key out, 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"

KEY adjective

Definition of key (adjective)

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"
   • synonyms: cardinal, central, fundamental, primal