A Quick and Simple Dictionary

key

1. Noun.  An object designed to open and close a lock.
2. Noun.  An object designed to fit between two other objects (such as a shaft and a wheel) in a mechanism and maintain their relative orientation.
3. Noun.  A crucial step or requirement.
4. Noun.  A guide explaining the symbols or terminology of a map or chart; a legend.
5. Noun.  A guide to the correct answers of a worksheet or test.
6. Noun.  (computing) One of several small, usually square buttons on a typewriter or computer keyboard, mostly corresponding to text characters.
7. Noun.  (music) One of a number of rectangular moving parts on a piano or musical keyboard, each causing a particular sound or note to be produced.
8. Noun.  (music) One of various levers on a musical instrument used to select notes, such as a lever opening a hole on a woodwind.
9. Noun.  (music) A hierarchical scale of musical notes on which a composition is based.
10. Noun.  (historical) A manual electrical switching device primarily used for the transmission of Morse code.
11. Noun.  (cryptography) A piece of information (e.g. a passphrase) used to encode or decode a message or messages.
12. Noun.  (computing) In a relational database, a field used as an index into another table (not necessarily unique).
13. Noun.  (computing) A value that uniquely identifies an entry in an associative array.
14. Noun.  (basketball) The free-throw lane together with the circle surrounding the free-throw line, the free-throw lane having formerly been narrower, giving the area the shape of a skeleton key hole.
15. Noun.  (biology) A series of logically organized groups of discriminating information which aims to allow the user to correctly identify a taxon.
16. Noun.  (slang) kilogram.
17. Adjective.  Indispensable.
18. Adjective.  Important, salient.
19. Verb.  To fit (a lock) with a key.
20. Verb.  To fit (pieces of a mechanical assembly) with a key to maintain the orientation between them.
21. Verb.  To mark or indicate with a symbol indicating membership in a class.
22. Verb.  (context, telegraphy and radio telegraphy) To depress (a telegraph key).
23. Verb.  (context, radio) To operate (the transmitter switch of a two-way radio).
24. Verb.  (computing) (''more usually'' '''to key in''') To enter (information) by typing on a keyboard or keypad.
25. Verb.  (colloquial) To vandalize (a car, etc.) by scratching with an implement such as a key.
26. Verb.  To link (as one might do with a key or legend).
27. Verb.  (intransitive) (biology, mostly) To be identified as a certain taxon when using a key.
28. Noun.  One of a string of small islands.