There are 2 main definitions of key in English:

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key 1

Pronunciation: /kiː/

noun (plural keys)

1A small piece of shaped metal with incisions cut to fit the wards of a particular lock, which is inserted into a lock and turned to open or close it: there were two keys to the cupboard a room key
More example sentences
  • In the recovery room and three theatres, the drugs cupboards had been opened using force and the metal cupboards inside had been opened with keys.
  • He pulled the keys out, opened the door and slammed it closed.
  • From her pockets, she produced a key and inserted the key into the door, opening it.
1.1A shaped metal implement for operating a switch in the form of a lock, especially one operating the ignition of a motor vehicle: Nat turned the key in the ignition
More example sentences
  • Anytime we flip a switch, turn a key in the ignition, or mail a letter, we expect something to happen.
  • He switched the keys in the ignition and the car started to roar.
  • When police stopped him his car engine was switched off and the keys were in the ignition and he was sitting in the driver's seat.
1.2An instrument for grasping and turning a screw, peg, or nut, especially one for winding a clock or turning a valve.
Example sentences
  • It later serviced the local textile industry, but then found a niche with the water industry, making valve keys for reservoirs and water mains.
  • The front of the tail mount is attached the keel and the back is elevated, plus there is no screw key below the keel.
  • Threats of police action to obtain the clock winding key were made recently.
1.3A pin, bolt, or wedge inserted into a hole or between parts so as to lock the parts together.
Example sentences
  • A cotter key fits in the two holes I drilled at the bottom and holds it open or shut.
  • Depending on the type of block you are using, there is typically some sort of key that locks one row to the row below it.
  • Opening the bubble-wrap we find the main unit, an instruction leaflet and a small bag with the screws and 2 keys.
2Each of several buttons on a panel for operating a computer, typewriter, or telephone: press the ENTER key
More example sentences
  • The participants initiated the trials by pressing any of the keys on the computer keyboard.
  • The function keys are smaller then normal, resembling the half-size keys found in many laptop keyboards.
  • To ensure that the computer remains in Standby, do not move the mouse or press any keys on your keyboard.
2.1A lever depressed by the finger in playing an instrument such as the organ, piano, flute, or concertina: a piece composed solely for the white keys on the piano
More example sentences
  • Her fingers stilled on the keys as the piano strings stopped their vibrations and the lounge was silent again.
  • The placement of the pianist's fingers on the keys also will affect dynamics to a certain degree.
  • Beth brought her fingers to the flute keys and played the first run of the piece.
2.2A lever operating a mechanical device for making or breaking an electric circuit, for example in telegraphy.
Example sentences
  • Using the Morse key, operators at the stations were able to communicate with the world 24 hours a day.
  • A woman sits at a telegraph key and rattles Morse code along a wire.
  • She had learned to shoot a pistol, crawl under barbed wire, tap out gibberish on a Morse key.
3A thing that provides a means of achieving or understanding something: discipline seems to be the key to her success
More example sentences
  • But as he explains, it is this hardship that provides a key to understanding the spirit and culture of these tribes.
  • Investment in higher education is the key to our future.
  • Universal responsibility is the real key to human survival.
answer, clue, solution, explanation, pointer, cue, lead;
condition, precondition, essential, means, way, route, path, passport, secret, formula;
guide, gloss, glossary, interpretation, explication, translation, clarification, exposition, annotation, index, legend, code
3.1An explanatory list of symbols used in a map, table, etc.
Example sentences
  • In fact, as will be obvious to any reader who has ever used an index, the symbols in the key refer to the chapters in which the characters appear.
  • References within the tables themselves are listed in a key below each individual Appendix.
  • There is extensive use of place names without accompanying maps throughout the book, and many of the maps provided lack keys and scales.
3.2A set of answers to exercises or problems: a key at the back of the book provides the answers
More example sentences
  • There are many ways of cheating on standardized tests other than doctoring the answer keys or even using questions from the test in class exercises.
  • If there are no answer keys, compare your answers against those of some friends of yours who are also doing the practice competitions.
  • The classroom teacher rated each test using answer keys, while the second author independently scored all tests.
3.3A word or system for solving a cipher or code: it took him some time to find the key, the connection between the code and the Odyssey
More example sentences
  • Quantum cryptography systems discard these corrupt keys and only use codes that are known to be secure.
  • The strongest of all cipher systems require a random key as long as the message that's being sent.
  • Cryptographic keys and iris code reside in the smart card.
3.4The first move in the solution of a chess problem.
Example sentences
  • The key is whether the defensive king can get within the promotion ‘square’.
3.5 Computing A field in a record which is used to identify that record uniquely.
Example sentences
  • The optional TYPE part of the foreign key name is used to support multiple keys to the same TABLE FIELD.
4 Music A group of notes based on a particular note and comprising a scale, regarded as forming the tonal basis of a piece of music: the key of E minor
More example sentences
  • Today, I am only going to listen to music played in major keys.
  • The pieces are all arranged as short, two-page pieces in the keys of C, F, G, D and B-flat major.
  • In my profession it may even be disadvantageous because it happens that we play a piece in a different key.
tone, pitch, timbre, tonality, tone colour, modulation
4.1The tone or pitch of someone’s voice: his voice had changed to a lower key
More example sentences
  • She tried to keep her voice down to a calm key.
  • Madame Lebrun was bustling in and out, giving orders in a high key to a yard-boy.
4.2The prevailing tone of a piece of writing, situation, etc. it was like the sixties all over again, in a new, more austerely intellectual key
More example sentences
  • Kingsley plays Ford in a near-hysterical key throughout, his jealousy tinged with full-blown paranoia.
  • The language of religion will return towards the end of his life, but in a different key, in his final collection of poems.
  • Burke comments in a more sombre key that ‘We may have spent several centuries not seeing the wood for the trees’.
style, character, mood, vein, spirit, feel, feeling, flavour, quality, humour, atmosphere
4.3The prevailing range of tones in a painting: these mauves, lime greens, and saffron yellows recall the high key of El Greco’s palette
More example sentences
  • The technique gives a high key but a reduced range of brightness.
  • Because of the dots and the diagonal lines and unmodulated color, I work in a color key that I love to play with.
  • Canaletto began to turn out views which were more topographically accurate, set in a higher key, and with smoother handling.
5The dry winged fruit of an ash, maple, or sycamore, typically growing in bunches; a samara.
Example sentences
  • Visitors were not allowed to use pens or pencils but to use other media such as twigs, sycamore keys and string, among other things, with Indian ink to make marks.
6The part of a first coat of wall plaster that passes between the laths and so secures the rest.
Example sentences
  • If the surface was primed with DG27, this first coat should be thick enough to cover over all of the key.
6.1The roughness of a surface, helping the adhesion of plaster or other material.
Example sentences
  • Scratch the render to form a key and, the next day, fill flush with a slightly weaker mix.
  • The nibs help to secure the plaster to the lattice, reinforcing the key or bond between plaster and wood.
  • Some rock lath was textured or perforated to provide a key for wet plaster.
7 Basketball The keyhole-shaped area marked on the court near each basket: he hit another jumper from the top of the key
More example sentences
  • The post player nearest the ball is the one to break and set a screen for the guard near the top of the key.
  • If you want, you can stand near the top of the key and make the players go around you.
  • Oregon retrieved the opening tip, and Flash dribbled down the court and hit a three from the top of the key.


Of crucial importance: she became a key figure in the suffragette movement
More example sentences
  • There are also moments when the emotional responses of key characters in key situations completely fail to ring true.
  • The Republicans also won a series of major victories in key congressional races.
  • His friendships with key figures in government go back decades.

verb (keys, keying, keyed)

[with object]
1Enter or operate on (data) by means of a computer keyboard or telephone keypad: she keyed in a series of commands [no object]: a hacker caused disruption after keying into a vital database
More example sentences
  • A digital image of the check is then taken and the system verifies the amount matches the one the customer keyed in.
  • Even in 2005, historical data sometimes has to be keyed in by hand!
  • The details will already be keyed into the computer and forwarded to the pharmacy of their choice.
2 [with object and adverbial] Fasten (something) in position with a pin, wedge, or bolt: the coils may be keyed into the slots by fibre wedges
More example sentences
  • With small machines, the core plates are keyed direct to the shaft.
  • Immovably keyed upon the cranked shaft is a heavy wooden cone pulley.
  • Since the crank is keyed to the pin, I'll have to arrange for each pin to come out of its main driver, rotated as far behind the vertical center-line as it is forward, then pressed back in.
3Roughen (a surface) to help the adhesion of plaster or other material: a wooden float with nails driven through it is used to key the wall surface between coats
More example sentences
  • Where no keying mix or bonding agent is specified, wet smooth concrete surfaces immediately before plastering.
  • If the piece is varnished or painted, sand it well to remove most of the finish and key the surface.
4Word (an advertisement in a periodical), typically by varying the form of the address given, so as to identify the publication generating particular responses: one keys advertisements and measures returns
More example sentences
  • But the firm makes much of its money from selling advertising space keyed to the words for which its users search.
5 informal Vandalize (a car) by scraping its paint with a key.
Example sentences
  • I couldn't come up with anything that wouldn't get my car keyed or otherwise vandalized in the middle of the night.
  • My car had been keyed and my kids had been verbally assaulted after accidentally hitting the neighbour's window with a snowball.
  • For the girl ranting about keying SUVs. I'm so glad you've decided to fight against people's destructive actions with such a constructive solution.
6North American informal Be the crucial factor in achieving: Ewing keyed a 73-35 advantage on the boards with twenty rebounds
More example sentences
  • Kaczowka keyed the offensive attack with 21 points and nine rebounds, while point guard Dani Langford contributed 15 points and eight assists.
  • Charleton's 23 points and Neufeld's 22 points keyed SFU's offensive attack.
  • The run was keyed by the re-entry into the game of forward Mike Sovran, a fifth year co-captain, who scored seven points in that span.


in (or out of) key

In (or out of) harmony: this uplifting conclusion is out of key with the body of his book
More example sentences
  • I mean, people singing along to songs, even horribly out of key, is better than groups of people talking loudly in some sort of strange choir.
  • Here, though, they're wavering, sliding in and out of key.
  • Every song is sure to be awesome and sung out of key.

Phrasal verbs


key someone/thing into (or in with)

Cause someone or something to be in harmony with: to those who are keyed into his lunatic sense of humour, the arrival of any Bergman movie is a major comic event
More example sentences
  • Beloved smells that key you into positive memories and experience can be all the difference you need.
  • Do it until a single word or image is enough to key you into that state of being - emulate Pavlov's dogs.
  • The issues that conference committees ask presenters to address can often key you into trends in the field.

key something to

chiefly North American Link something to: courses keyed to the needs of health professionals
More example sentences
  • For texts which authors and publishers wish to keep free of superscript symbols, endnotes are keyed to such points of reference as page numbers or repeat identifying phrases from the text.
  • The extensive end notes are keyed to each chapter.
  • The interest rate may go up or down over the years, and it is keyed to a financial market index.

be keyed up

Be nervous, tense, or excited, especially before an important event: he was keyed up at the thought of seeing Rosemary
More example sentences
  • I allowed myself to be keyed up and nervous before I got here, but now I am here I focus on the business.
  • The 28th Division was keyed up by a visit and inspection from their boss Eisenhower, certain in the knowledge that they were to be among the first to assault France.
  • And there's another reason why Priaulx is keyed up about the races at his home track: ‘I spent a long time at Silverstone as an instructor.’



Example sentences
  • The managers went around the keyers tonight trying to find volunteers to man the lines.
  • They are full linear keyers that offer many of the same features found on high-end production switchers.
  • The average annual salary for Data entry keyers in Rhode Island was $26,490 per year.


Pronunciation: /ˈkiːləs/
Example sentences
  • Ultimately, I think true keyless access will require an implantable chip with a very strong encryption system; right now I'm only looking at this in a personal context.
  • Among the features which make Micra stand out are sliding rear seats to maximise cabin space, a keyless ignition system and storage space under the passenger seat.
  • Honda's Stream is also fitted with an engine immobiliser, alarm system and remote keyless entry.


Old English cǣg, cǣge, of unknown origin.

  • quay from Late Middle English:

    One of those words that seems designed to trip up poor spellers, this word was originally spelt as it is pronounced, key. It comes from Old French kay, of Celtic origin. The change of spelling occurred in the late 17th century, influenced by the modern French spelling quai. Cay or key for a sand bar is the same word.

Words that rhyme with key

absentee, açai, addressee, adoptee, agree, allottee, amputee, appellee, appointee, appraisee, après-ski, assignee, asylee, attendee, bailee, bain-marie, Bangui, bargee, bawbee, be, Bea, bee, bootee, bouquet garni, bourgeoisie, Brie, BSc, buckshee, Capri, cc, chimpanzee, cohabitee, conferee, consignee, consultee, Cree, debauchee, decree, dedicatee, Dee, degree, deportee, dernier cri, detainee, devisee, devotee, divorcee, draftee, dree, Dundee, dungaree, eau-de-vie, emcee, employee, endorsee, en famille, ennui, enrollee, escapee, esprit, evacuee, examinee, expellee, fee, fiddle-de-dee, flea, flee, fleur-de-lis, foresee, franchisee, free, fusee (US fuzee), Gardaí, garnishee, gee, ghee, glee, goatee, grandee, Grand Prix, grantee, Guarani, guarantee, he, HMRC, indictee, inductee, internee, interviewee, invitee, jamboree, Jaycee, jeu d'esprit, knee, Lea, lee, legatee, Leigh, lessee, Ley, licensee, loanee, lychee, manatee, Manichee, maquis, Marie, marquee, me, Midi, mortgagee, MSc, nominee, obligee, Otomi, parolee, Parsee, parti pris, patentee, Pawnee, payee, pea, pee, permittee, plc, plea, pledgee, pollee, presentee, promisee, quay, ratatouille, referee, refugee, releasee, repartee, retiree, returnee, rupee, scot-free, scree, sea, secondee, see, settee, Shanxi, Shawnee, shchi, she, shea, si, sirree, ski, spree, standee, suttee, tant pis, tea, tee, tee-hee, Tennessee, testee, the, thee, three, thuggee, Tiree, Torquay, trainee, Tralee, transferee, tree, Trincomalee, trustee, tutee, twee, Twi, undersea, vestee, vis-à-vis, wagon-lit, Waikiki, warrantee, we, wee, whee, whoopee, ye, yippee, Zuider Zee
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There are 2 main definitions of key in English:

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key 2

Pronunciation: /kiː/


A low-lying island or reef, especially in the Caribbean. Compare with cay.
Example sentences
  • Now, you'll appreciate that the Bahamas is an island chain of more than 700 islands and keys.
  • These flat and unexceptional little keys, just south of Cuba in the Northern Caribbean, enjoy the status of a tax haven.
  • He was sentenced to life imprisonment at Fort Jefferson, a huge fort in the Dry Tortugas, islands 70 miles off the Florida keys.


Late 17th century: from Spanish cayo 'shoal, reef', influenced by quay.

  • quay from Late Middle English:

    One of those words that seems designed to trip up poor spellers, this word was originally spelt as it is pronounced, key. It comes from Old French kay, of Celtic origin. The change of spelling occurred in the late 17th century, influenced by the modern French spelling quai. Cay or key for a sand bar is the same word.

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