1 key /ˈkiː/ noun
plural keys
1 key
plural keys
Learner's definition of KEY
: a device that is used to open a lock or start an automobile
◊ The usual type of key is a small metal object that you insert into a narrow opening and turn.
often used figuratively see also latchkey, passkey, skeleton key
: a device that looks like a key and that is used to turn something
: something that is necessary in order to do or achieve something usually singular
usually + to
: something that provides an explanation or solution usually + to
: a list of words or phrases that explain the meaning of symbols or abbreviations
: any one of the buttons of a computer or typewriter that you push with your fingers see picture at computer; see also function key, shift key
: any one of the parts that you push with your fingers to play a piano or similar musical instrument
music : a system of musical tones based on a scale beginning on the note for which the system is named

under lock and key

see 1lock
compare 4key
2 key /ˈkiː/ adjective
2 key
Learner's definition of KEY
: extremely important
3 key /ˈkiː/ verb
keys; keyed; keying
3 key
keys; keyed; keying
Learner's definition of KEY
[+ object]
: to enter (information) by using the keys of a computer, typewriter, etc.
often + in
often + into
US, informal : to have the most important part in (something)

key to

[phrasal verb] chiefly US
key (something) to (something or someone) : to make (something) suitable for (a particular use or type of person) often used as (be) keyed to
key (something) to (something) : to change (something) in a way that is closely related to (something else) usually used as (be) keyed to
4 key /ˈkiː/ noun
plural keys
4 key
plural keys
Learner's definition of KEY
[count] : a low island or reef
the Keys : a group of small islands off the southern coast of Florida
compare 1key
Comments & Questions
Comments & Questions
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