key

1 of 5

noun (1)

plural keys
1
a
: a usually metal instrument that is used to open a lock or to start or access a mechanism
my house/car keys
turned the key in the lock/ignition
… a metallic rattle, like keys being jangled.Derwent May
b
: something that resembles a key in form or function
a key for winding a clock
A computer chip-based ignition key that relies on a wireless connection to your car …Dustin Hawley
By using their smartphone, … guests are able to … download a room key.Sharon Love
see also key card, key fob
2
a
: a means of gaining or preventing entrance, possession, or control
b
: an instrumental or deciding factor
the key to her success
3
a
: 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
d
: an arrangement of the salient characters of a group of plants or animals or of taxa designed to facilitate identification
e
: a map legend
4
a
: 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
6
a
: 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
11
a(1)
(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
keyed adjective
keyless adjective

key

2 of 5

adjective

: extremely or crucially important
key issues
a key moment in the game
a key member of the staff

key

3 of 5

verb

keyed; keying; keys

transitive verb

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 drawingsJohn Gartner
6
: to make nervous, tense, or excited
usually used with up
was 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 into
key in a password
information 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

intransitive verb

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 on
The middle linebacker was keying on the halfback.
3
: to operate a machine by means of a keyboard : keyboard

key

4 of 5

noun (2)

: a low island or reef
specifically : any of the coral islets off the southern coast of Florida
the Florida Keys

key

5 of 5

noun (3)

slang
: a kilogram especially of marijuana or heroin

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 See More
Recent Examples on the Web
Adjective
Qatar and Egypt have played key roles in the negotiations. Ken Thomas, WSJ, 23 Nov. 2023 For male actor in a leading role, true stories seem to be key. Emily Longeretta, Variety, 22 Nov. 2023 Choosing a kit that’s safe, fun, and reflective of their interests is key. Cheryl Fenton, Parents, 22 Nov. 2023 Assign Your Tasks Levels of Priority Making a set of priorities and layering those priorities are key. Rolling Stone Culture Council, Rolling Stone, 22 Nov. 2023 Those hourly reports were a key metric for a congregation’s spiritual vitality and a factor in deciding who rose to leadership. Peter Smith, Fortune, 22 Nov. 2023 Low pay has long been a key factor in the shortage of child care — a problem compounded by how little the state pays providers of subsidized care. San Diego Union-Tribune, 22 Nov. 2023 Whether that will change is a key concern for Johnson, who is already beginning to run out of time before the 2024 election chooses the next House. Jacob Bogage, Washington Post, 21 Nov. 2023 Israel has said Hamas runs a key command center underneath the hospital, and Israeli troops inside Gaza City are now about one mile from the hospital complex, raising fears among Gazans that the hospital will be attacked and prompting an evacuation of the majority of people on Friday. Chao Deng, WSJ, 11 Nov. 2023
Verb
It’s been written many times that fall is prime to upsize to bigger lures and flies because the fish are more keyed into big meals, but that’s not entirely accurate. Joe Cermele, Field & Stream, 2 Nov. 2023 Bloys also keyed in on commenters on Deadline articles. Winston Cho, The Hollywood Reporter, 1 Nov. 2023 Parker’s offense is keyed by QB Malik Muhammad with A’mari Brundidge and Martavius Purnell handling the load at RB. Dennis Victory, al, 29 Aug. 2023 The second-year pro helped set up Stafford’s third-quarter touchdown pass to Kupp, rushed for a fourth-quarter touchdown and keyed a field-goal drive before leaving the game because of an ankle injury. Gary Klein, Los Angeles Times, 15 Oct. 2023 The customer keys in a digital order, a bowl shoots down and the ingredients are dispensed from above. Laura Reiley, Washington Post, 3 Oct. 2023 The senior keyed a defense that allowed only four goals. Steve Brand, San Diego Union-Tribune, 16 Oct. 2023 On their next possession, Williams’ 31-yard run keyed an 80-play drive that ended with another Brett Maher field goal for a 16-9 lead. Gary Klein, Los Angeles Times, 15 Oct. 2023 Alabama sticks at No. 5 after an easy win against Middle Tennessee keyed by a very solid starting debut for quarterback Jalen Milroe. Paul Myerberg, USA TODAY, 5 Sep. 2023
Noun
The boys need their father’s keys, but don’t have time to fetch them. Jennifer Ouellette and Sean M. Carroll, Ars Technica, 24 Nov. 2023 The key is developing effective methods of suppressing and correcting quantum errors, an area my own research is focused on. Daniel Lidar, Discover Magazine, 23 Nov. 2023 Video shows Ricci dropping his keys and a to-go drink and, in seconds, pulling a handgun from his waist and shooting as the men ran away. Salvador Hernandez, Los Angeles Times, 21 Nov. 2023 Most of our styles have several inner and outer pockets to keep stuff, D-rings to keep keys or AirPods cases and so on. Laird Borrelli-Persson, Vogue, 21 Nov. 2023 But the key is using available technology and best practices to diagnose a specific patient, so that treatment can be determined. Stanley Goldfarb, National Review, 21 Nov. 2023 The key is that AI needs to be developed and deployed so all businesses and workers can benefit from it. Rhett Buttle, Forbes, 13 Nov. 2023 The key is that regulatory efforts build adaptive capacity, learning lessons from yesterday and today to help prepare us for tomorrow. Paula Goldman, Foreign Affairs, 13 Nov. 2023 Chaudry tells Rolling Stone that the key is for creators to really connect with their viewers, in order to turn their content into a living. Ct Jones, Rolling Stone, 12 Nov. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'key.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Noun (1), Adjective, and Verb

Middle English, from Old English cǣg; akin to Old Frisian kēi key

Noun (2)

Spanish cayo, from Taino

Noun (3)

by shortening & alteration from kilo

First Known Use

Noun (1)

before the 12th century, in the meaning defined at sense 1a

Adjective

1832, in the meaning defined above

Verb

14th century, in the meaning defined at transitive sense 1

Noun (2)

1693, in the meaning defined above

Noun (3)

1966, in the meaning defined above

Time Traveler
The first known use of key was before the 12th century

Dictionary Entries Near key

Cite this Entry

“Key.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/key. Accessed 28 Nov. 2023.

Kids Definition

key

1 of 4 noun
plural keys
1
a
: a small device that is used to open a lock or start an automobile
b
: a device having the form or function of a key
a key for winding a clock
2
: a means of gaining or preventing entrance, possession, or control
3
a
: something that provides an explanation, solution, or means of identifying
the key to a riddle
b
: a series of phrases or statements that describe characteristics by which plants or animals of a particular group differ and are used to aid in identification
c
: a map legend
4
: one of the levers with a flat surface that is pressed by a finger in operating a machine or playing an instrument
5
: a system of seven musical tones arranged in relation to a keynote from which the system is named
the key of C
6
: a characteristic style or tone
7
: a small switch for opening or closing an electric circuit

key

2 of 4 verb
keyed; keying
1
: to adjust the musical pitch of
2
: to bring into harmony
3
: to make nervous, tense, or excited
usually used with up
all keyed up about the test
4
: to record by operating the keys of a machine
key each price into the cash register

key

3 of 4 adjective
: of great importance
the key people in the organization
the key question is "Can we afford it?"
use key words in an outline

key

4 of 4 noun
: a low island or reef
the Florida Keys
Etymology

Noun

Old English cǣg "key"

Noun

from Spanish cayo "a low island or reef"

Legal Definition

key

adjective
: 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

Biographical Definition

Key 1 of 2

biographical name (1)

Francis Scott 1779–1843 American lawyer and author of "The Star-Spangled Banner"

Key

2 of 2

biographical name (2)

John (Phillip) 1961–     prime minister of New Zealand (2008–16)

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