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
Recent Examples on the Web
Adjective
Billboard’s Friday Music Guide serves as a handy guide to this Friday’s most essential releases — the key music that everyone will be talking about today, and that will be dominating playlists this weekend and beyond. Jason Lipshutz, Billboard, 15 Mar. 2024 Another key recommendation is to slow down while eating and listen to fullness cues, said Yancy. Kristen Fischer, Health, 15 Mar. 2024 Senegal’s authorities freed two key opposition leaders from prison, boosting the anti-establishment campaign before this month’s presidential elections. Katarina Hoije, Bloomberg.com, 15 Mar. 2024 In the end, the prosecution got them all — son, mother and father — the three key figures in a 2021 mass school shooting that cost four students their lives, heightened awareness about parental responsibility and proper gun storage, and made history in the world of American jurisprudence. Tresa Baldas, Detroit Free Press, 15 Mar. 2024 Another key finding is 92% of respondents said their organizations should do more to leverage financial and operational data to inform strategic decisions. Sheryl Estrada, Fortune, 15 Mar. 2024 They are also required to contain important key minerals for infant growth and development, like iron. Lainey Younkin, Ms, Rd, Parents, 15 Mar. 2024 Kwong says the key factor in making delicious at-home tanghulu is temperature control. Steffi Cao, Bon Appétit, 15 Mar. 2024 If the measure were to pass this month, TikTok’s Chinese parent company, ByteDance, would be forced to sell the app by September, two months before voters head to the ballot box — and Democrats are reliant upon young voters to goose turnout in key swing districts. Aaron Schaffer, Washington Post, 15 Mar. 2024
Verb
Democrats have attempted to paint Hovde as an out-of-touch millionaire attempting to buy a Senate seat in Wisconsin, keying in on his business ties to California. Lawrence Andrea, Journal Sentinel, 20 Feb. 2024 But the other to key in on, too, independents, Trump will get that with a 19-point advantage. Nbc Universal, NBC News, 4 Feb. 2024 Unselfish basketball keyed that spurt with three assists on the four baskets. Jacob Steinberg, Baltimore Sun, 19 Jan. 2024 One factor quietly keying the surge has been the steady play of point guard Kris Dunn. John Coon, USA TODAY, 18 Jan. 2024 McCarthy's talent is evident when in command of an offense, and some draft experts have keyed him in to be a first round draft pick, while others see Michigan's quarterback falling to Day 2 of the drat. Sahil Kurup, Detroit Free Press, 8 Jan. 2024 Introduce Them To Key Stakeholders Introduce new staff members to key external stakeholders in a meet and greet activity. Expert Panel®, Forbes, 29 Feb. 2024 Keyshawn Hall added 17 points for the Patriots (18-8, 7-6 Atlantic 10), who trailed 40-29 early in the second half before their physical defense keyed a 24-2 run that had Skinn asking the boisterous home crowd to get even louder. Ben Nuckols, USA TODAY, 22 Feb. 2024 For all its fizzing energy, this is a sorrowful film — sorry for the girls, sorry for the guys — keyed into the sadness that lurks in day-glo places, pool parties, dance podiums and the overlit cosmetics aisle of an airport duty-free shop. Jessica Kiang, Los Angeles Times, 2 Feb. 2024
Noun
The key is to carefully apply thin coats between curing. Kate Watson, Peoplemag, 16 Mar. 2024 The America First Policy Institute, a think tank promoting Trump’s vision, said the key is to cut government borrowing to reduce mortgage rates. Josh Boak, Fortune, 15 Mar. 2024 When the class trip was over, Cox returned to her car but the key would not work. Claire Lempert, ABC News, 15 Mar. 2024 But that key can’t be used to decrypt their messages. Robin Chataut, Discover Magazine, 15 Mar. 2024 Another key will be finding ways to get the ball to Jaedon LeDee, who had a season-low 12 points on 2 of 12 shooting facing a collapsing defense backed by 6-7, 260-pound Rob Whaley Jr. Mark Zeigler, San Diego Union-Tribune, 14 Mar. 2024 The electric blue of Florida’s keys provide a fresh, picturesque backdrop to a lot of B movie pulp, but the rest is properly familiar. David Fear, Rolling Stone, 9 Mar. 2024 He was followed to a nearby creek, where many of the missing items, including two laptops and a set of keys, were found. Nollyanne Delacruz, The Mercury News, 8 Mar. 2024 For the Jayhawks, the key will be to put Dajuan Harris on him and take the ball out of his hands. Shreyas Laddha, Kansas City Star, 5 Mar. 2024

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 29 Mar. 2024.

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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