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\ ˈkē 
\
\Definition of key
(Entry 1 of 7)
1a : a usually metal instrument by which the bolt of a lock is turned
b : any of various devices having the form or function of such a key
a key for winding a clock
2a : a means of gaining or preventing entrance, possession, or control
b : an instrumental or deciding factor
the key to her success
3a : something that gives an explanation or identification or provides a solution
the key to a riddle
b : a list of words or phrases giving an explanation of symbols or abbreviations
a pronunciation key in a dictionary
c : an aid to interpretation or identification : clue a key to understanding their motivation
e : a map legend
4a : a part to be depressed by a finger that serves as one unit of a keyboard also : a representation of such a key (such as a space delineated on a touch screen) Tiny keys on your iPhone's screen can be difficult to hit accurately. — Cherlynn Low
b : one of the levers of a keyboard musical instrument that actuates the mechanism and produces the tones
c : a lever that controls a vent in the side of a woodwind instrument or a valve in a brass instrument
5 : a system of tones and harmonies generated from a hierarchical scale of seven tones based on a tonic
the key of G major
6a : characteristic style or tone
b : the tone or pitch of a voice
c : the predominant tone of a photograph with respect to its lightness or darkness
7 : a decoration or charm resembling a key
8 : a small switch for opening or closing an electric circuit
a telegraph key
9 : the set of instructions governing the encipherment and decipherment of messages
an encryption key
10 : a free-throw area in basketball : free throw lane a jump shot from the top of the key
11a(1) : cotter pin
(2) : cotter
b : a keystone in an arch
c : a small piece of wood or metal used as a wedge or for preventing motion between parts
12 : samara
key
adjectiveDefinition of key (Entry 2 of 7)
: extremely or crucially important
key issues a key moment in the game a key member of the staff
key
verbkeyed; keying; keys
Definition of key (Entry 3 of 7)
1 : to lock or secure with or as if with a key : fasten: such as
a : to secure (something, as a pulley on a shaft) by a key
b : to finish off (an arch) by inserting a keystone
2 : to regulate the musical pitch of
key the strings
3 : to bring into harmony or conformity : make appropriate : attune remarks keyed to a situation
4 : to identify (a biological specimen) by a key (see key entry 1 sense 3d)
5 : to provide with identifying or explanatory cross-references
instructions keyed to accompanying drawings— John Gartner
6 : to make nervous, tense, or excited
—usually used with upwas too keyed up to sleep
7 : to enter or input (text or data) by using a keyboard
keying changes to a manuscript —often used with in or intokey in a passwordinformation being keyed into a database
8 : to be essential to : play the most important part in
defense keyed the victory
9 : to vandalize by scratching with a key
someone keyed my car door
1 : to use a key
2 : to observe the position or movement of an opposing player in football in order to anticipate the play
—usually used with onThe middle linebacker was keying on the halfback.
3 : to operate a machine by means of a keyboard : keyboard
key
noun (2)Definition of key (Entry 4 of 7)
: a low island or reef specifically : any of the coral islets off the southern coast of Florida the Florida Keys
key
noun (3)Definition of key (Entry 5 of 7)
slang
: a kilogram especially of marijuana or heroin
Key
biographical name (1)\ ˈkē \
\Definition of Key (Entry 6 of 7)
Francis Scott 1779–1843 American lawyer and author of "The Star-Spangled Banner"
Key
biographical name (2)Definition of Key (Entry 7 of 7)
John (Phillip) 1961– prime minister of New Zealand (2008–16)
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Other Words from key
Noun (1)
keyed \ ˈkēd \ adjective
\ adjectivekeyless \ ˈkē-ləs \ adjective
\ adjectiveSynonyms & Antonyms for key
Synonyms: Adjective
- arch,
- big,
- capital,
- cardinal,
- central,
- chief,
- dominant,
- first,
- foremost,
- grand,
- great,
- greatest,
- highest,
- leading,
- main,
- master,
- number one
- (also No. 1),
- numero uno,
- overbearing,
- overmastering,
- overriding,
- paramount,
- predominant,
- preeminent,
- premier,
- primal,
- primary,
- principal,
- prior,
- sovereign
- (also sovran),
- supreme
Synonyms: Verb
Antonyms: Adjective
Antonyms: Verb
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Examples of key in a Sentence
Adjective
He's a key player in the organization.
The key question is “Can we afford it?”.
Underline key words and phrases as you read.
Their votes were key in getting the bill passed. Verb
The changes to the manuscript are being keyed by the typist.
her response was perfectly keyed to the situation
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More Definitions for key
key
verbEnglish Language Learners Definition of key (Entry 2 of 2)
: to enter (information) by using the keys of a computer, typewriter, etc.
US, informal : to have the most important part in (something)
See the full definition for key in the English Language Learners Dictionary
key
noun\ ˈkē \
\Kids Definition of key
(Entry 1 of 4)
1 : an instrument by which the bolt of a lock (as on a door) is turned or by which an engine is started
2 : a device having the form or function of a key
Can you wind the clock with the key?
3 : the thing that is necessary or most important in doing something
To learn a skill, practice is the key.
4 : something (as a map legend) that gives an explanation : solution
5 : one of the levers with a flat surface that is pressed with a finger to activate a mechanism of a machine or instrument
computer keys
6 : a system of seven musical tones arranged in relation to a keynote from which the system is named
the key of C
key
verbkeyed; keying
Kids Definition of key (Entry 2 of 4)
1 : to regulate the musical pitch of
2 : to bring into harmony
3 : to record or enter by operating the keys of a machine
The cashier keyed in the price.
key
adjectiveKids Definition of key (Entry 3 of 4)
: of great importance : most important
She is one of our key players.
key
nounKids Definition of key (Entry 4 of 4)
: a low island or reef
the Florida Keys
key
adjectiveLegal Definition of key
: of vital importance (as in a business organization) especially so as to be specially insured to the benefit of an employer
key man key employee insurance
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Time Traveler for key
The first known use of key was before the 12th century
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