key
Language: English
Part of speech: noun
Pronunciation: enpr: kē
ipa: /kiː/
ipa: /ki/
rhymes: -iː
homophone: cay
homophone: ki
homophone: quay
Forms: form: keys
Etymology: From Middle English keye, kaye, keiȝe, from Old English cǣġ (“key, solution, experiment”) (whence also Scots key and kay (“key”)), of uncertain origin. The only sure cognates are Saterland Frisian Koai (“key”), West Frisian kaai (“key”), and North Frisian kai, koie (“key”). Possibly from Proto-Germanic *kēgaz, *kēguz (“stake, post, pole”), from Proto-Indo-European *ǵogʰ-, *ǵegʰ-, *ǵegʰn- (“branch, stake, bush”), which would make it cognate with Middle Low German kāk (“whipping post, pillory”), and perhaps to Middle Dutch keige (“javelin, spear”) and Middle Low German keie, keige (“spear”).
For the semantic development, note that medieval keys were simply long poles (ending in a hook) with which a crossbar obstructing a door from the inside could be removed from the outside, by lifting it through a hole in the door. Liberman has noted, however, "The original meaning of *kaig-jo- was presumably '*pin with a twisted end.' Words with the root *kai- followed by a consonant meaning 'crooked, bent; twisted' are common only in the North Germanic languages."
Senses: examples: text: We tiptoed into the house, up the stairs and along the hall into the room where the Professor had been spending so much of his time. 'Twas locked, of course, but the Deacon man got a big bunch of keys out of his pocket and commenced to putter with the lock.
ref: 1913, Joseph C[rosby] Lincoln, chapter XIII, in Mr. Pratt’s Patients, New York, N.Y.; London: D[aniel] Appleton and Company, →OCLC:
glosses: An object designed to open and close a lock.
hypernyms: part#Noun
component#Noun
related: word: keyway
word: keyseat#Noun
coordinate_terms: spline
spline
feather
glosses: An object designed to fit between two other objects (such as a shaft and a wheel) in a mechanism and maintain their relative orientation.
examples: text: The key to solving this problem is persistence.
text: the key to winning a game
text: Those who are accustomed to reason have got the true key of books.
ref: a. 1705, John Locke, “Of the Conduct of the Understanding”, in Posthumous Works of Mr. John Locke: […], London: […] A[wnsham] and J[ohn] Churchill, […], published 1706, →OCLC:
text: who keeps the keys of all the creeds
ref: 1850, [Alfred, Lord Tennyson], “(please specify |part=Prologue or Rpilogue, or |canto=I to CXXIX)”, in In Memoriam, London: Edward Moxon, […], →OCLC:
text: The PEOPLE'S DAILY today front pages a news item in column one in the experience of Yuhsi County in Yunnan which "mastered the law of agricultural field management, and found the key to increasing autumn grain production."
ref: 1960 August 29 [1960 August 26], “Higher Autum Grain Yield is Possible”, in Daily Report: Foreign Radio Broadcasts, number 168, Foreign Broadcast Information Service, sourced from Peking NCNA, translation of original in Chinese, →OCLC, Communist China: National Affairs, page BBB 2-BBB 3:
glosses: A crucial step or requirement.
examples: text: The key says that A stands for the accounting department.
glosses: A small guide explaining symbols or terminology, especially the legend on a map or chart.
examples: text: Some students cheated by using the answer key.
glosses: A guide to the correct answers of a worksheet or test.
examples: text: Press the Escape key.
topics: computing
engineering
mathematics
natural-sciences
physical-sciences
sciences
glosses: One of several small, usually square buttons on a typewriter or computer keyboard, mostly corresponding to text characters.
topics: entertainment
lifestyle
music
glosses: In musical instruments, one of the valve levers used to select notes, such as a lever opening a hole on a woodwind.
topics: entertainment
lifestyle
music
glosses: In instruments with a keyboard such as an organ or piano, one of the levers, or especially the exposed front end of it, which are depressed to cause a particular sound or note to be produced.
examples: text: the key of B-flat major
text: A girl, it is true, has always lived in a glass house among reproving relatives, whose word was law; she has been bred up to sacrifice her judgments and take the key submissively from dear papa; and it is wonderful how swiftly she can change her tune into the husband's.
ref: 1881, R.L. Stevenson, Virginibus Puerisque:
topics: entertainment
lifestyle
music
glosses: A scale or group of pitches constituting the basis of a musical composition.
topics: entertainment
lifestyle
music
glosses: A scale or group of pitches constituting the basis of a musical composition.
The lowest note of a scale; keynote.
topics: entertainment
lifestyle
music
glosses: A scale or group of pitches constituting the basis of a musical composition.
In musical theory, the total melodic and harmonic relations, which exist between the tones of an ideal scale, major or minor; tonality.
topics: entertainment
lifestyle
music
glosses: A scale or group of pitches constituting the basis of a musical composition.
In musical theory and notation, the tonality centering in a given tone, or the several tones taken collectively, of a given scale, major or minor.
topics: entertainment
lifestyle
music
glosses: A scale or group of pitches constituting the basis of a musical composition.
In musical notation, a sign at the head of a staff indicating the musical key.
examples: text: 2. Queen.[…]Deere Glasse of Ladies
Bid him that we whom flaming war doth scortch,
Vnder the shaddow of his Sword, may coole us:
Require him he advance it ore our heades;
Speak't in a womans key: like such a woman
As any of us three; weepe ere you faile; lend us a knee;
But touch the ground for us no longer time
Then a Doves motion, when the head's pluckt off:
Tell him if he i'th blood cizd field, lay swolne
Showing the Sun his Teeth; grinning at the Moone
What you would doe.
ref: 1613–1614 (date written), John Fletcher, William Shak[e]speare, The Two Noble Kinsmen: […], London: […] Tho[mas] Cotes, for Iohn Waterson; […], published 1634, →OCLC, Act I, scene i, page 1:
text: ?, William Cowper, Conversation
You fall at once into a lower key.
glosses: The general pitch or tone of a sentence or utterance.
examples: text: Another popular way to key ads and mailings is to use a suite number, room number, department number, desk number, etc. as part of the ordering address. With a classified ad, using such a key may increase your ad cost.
ref: 1998, Mail Order Success Secrets:
topics: advertising
business
marketing
glosses: A modification of an advertisement so as to target a particular group or demographic.
topics: biology
botany
natural-sciences
glosses: An indehiscent, one-seeded fruit furnished with a wing, such as the fruit of the ash and maple; a samara.
glosses: A manual electrical switching device primarily used for the transmission of Morse code.
topics: computing
cryptography
engineering
mathematics
natural-sciences
physical-sciences
sciences
glosses: A piece of information (e.g., a password or passphrase) used to encode or decode a message or messages.
examples: text: if you know someone who is in the channel, you can query them and ask for the key.
ref: 2000, Robert Erdec, “Re: Help; mIRC32; unable to resolve server arnes.si”, in alt.irc.mirc (Usenet):
glosses: A password restricting access to an IRC channel.
topics: computing
databases
engineering
mathematics
natural-sciences
physical-sciences
sciences
glosses: In a relational database, a field used as an index into another table (not necessarily unique).
topics: computing
engineering
mathematics
natural-sciences
physical-sciences
sciences
glosses: A value that uniquely identifies an entry in a container.
examples: text: radiator key
text: clock key
text: hex key
text: Torx key
glosses: Any of various tools comparable to a wrench (spanner) or driver, or, in some cases, also called a wrench or driver.
topics: biology
natural-sciences
glosses: A series of logically organized groups of discriminating information which aims to allow the user to correctly identify a taxon.
topics: architecture
glosses: A piece of wood used as a wedge.
topics: architecture
glosses: The last board of a floor when laid down.
topics: business
construction
manufacturing
masonry
glosses: A keystone.
glosses: That part of the plastering which is forced through between the laths and holds the rest in place.
topics: rail-transport
railways
transport
glosses: A wooden wedge, driven sideways between a bullhead rail and a cast-iron chair, to keep the rail securely in position.
examples: text: The door panel should be sanded down carefully to provide a good key for the new paint.
glosses: The degree of roughness, or retention ability of a surface to have applied a liquid such as paint, or glue.
topics: cartomancy
human-sciences
mysticism
philosophy
sciences
glosses: The thirty-third card of the Lenormand deck.
qualifier: print and film
glosses: The black ink layer, especially in relation to the three color layers of cyan, magenta, and yellow. See also CMYK.
examples: text: You can easily create this type of user interface by creating a bitmap with certain portions set to a predefined color you want to use as the transparency key.
ref: 2004, Mark Schmidt, Simon Robinson, Microsoft Visual C# .NET 2003 Developer's Cookbook, page 195:
text: There are key controls that adjust the “slice level” or the level at which the key kicks-in and starts cutting a hole for the “fill” […] Chroma key is another form of keying, which derives the key cutter or hole from a selected color.
ref: 2016, Jerry C. Whitaker, The SBE Broadcast Engineering Handbook:
topics: broadcasting
computer-graphics
computing
engineering
mathematics
media
natural-sciences
physical-sciences
sciences
television
glosses: A color to be masked or made transparent.
examples: text: He shoots from the top of the key.
topics: ball-games
basketball
games
hobbies
lifestyle
sports
glosses: The free-throw lane together with the circle surrounding the free-throw line, the free-throw lane having formerly been narrower, giving the area the shape of a skeleton key hole.
examples: text: "It just means that one of them here and there will need to play on a small-to-medium forward (instead of Riewoldt) which is fine. Our keys are pretty agile."
ref: 2023 April 7, “'Bit of a surprise': Dogs bemused by Tigers' selection call”, in Australian Football League, retrieved 27 Jul 2025:
qualifier: Australian rules football
glosses: A key position player (a tall forward or defender).
Hyponyms: candidate key
card key
church key
database key
Escape key
Esc key
foreign key
keyphrase
keyword
major key
minor key
Morse key
passcode
passphrase
password
primary key
silent key
skeleton key
unique key
Derived terms: accelerator key
a golden key can open any door
Allen key
alt key
answer key
arrow key
autokey
barrel key
bedkey
bis key
boss key
bump key
business key
card key
car key
CD key
change key
check key
Chinese keys
chroma-key
chroma key
chuck key
clustering key
Command key
composite key
compound key
content key
control key
Cross Keys
Cuban Keys
culverkey
cursor key
dead key
dichotomous key
disk on key
electronic car key
enter key
escape key
false key
fin key
function key
Greek key
hashkey
hex key
high-key
home key
hotkey
hot key
housekey
identification key
ignition key
I lost my keys
in a major key
in a minor key
in key
I've lost my keys
jiggle key
jiggler key
keyable
key alike
key back
key bed
keybed
keybind
key binding
key bit
keyboard
key bolt
key bounce
keybounce
keyboy
key-bugle
key bump
keybutton
keycap
keycard
keychain
keyclick
key club
keycode
key-cold
key combo
key currency
key defender
key desk
key down
key drive
keyer
key exchange
key finder
keyfob
key forward
key frame
keyframe
key-fruit
key fruit
Key Green
key grip
keyguard
key harp
keyholder
key holder
keyholding
keyhole
key interest rate
key into
keykeeper
key-keeper
Key Largo
keyless
keylet
key light
keylike
keyline
keylock
key log
key logger
keylogger
keylogging
keymaker
keyman
key man risk
keymap
keymapping
keymask
keymaster
key-money
key money
keyness
keynote
key of the door
Key of the Mediterranean
key of the street
keypad
key pair
keypair
keypal
key party
keypath
key performance indicator
key person insurance
key person risk
keyphone
keyplate
keypoint
keypress
key press
keypunch
key rate
keyring
keyscan
keyseat
key seat
keysender
keysending
key server
keyserver
keyset
key set identifier
keysigning
keysmash
keysmith
keys of the kingdom
keyspace
key spoke
key stage
keystone
keystore
keys to the kingdom
keystream
key stretching
keystring
keystrip
keystroke
keyswitch
keytainer
keytap
keytop
key to the city
key to the door
key to the midway
key up
key-value
keyway
keyword
key-word
key word
keywork
keyworker
key worker
key wrench
latchkey
latch key
latch-key
latch-key child
lock key
lock someone up and throw away the key
low key
lowkey
low-key
maple key
master key
meta key
mid-key
miskey
modifier key
multikey
natural key
nose key
off-key
out of key
parallel key
passkey
PF key
piano keys
pipe key
pre-shared key
private key
programmed function key
public key
public key certificate
public key cryptography
railway key
rekey
relative key
return key
rose key
screw key
serial key
shift key
shortcut key
skate key
slack key
slack-key
soft key
sortkey
split key
spoke key
start key
stream key
subkey
sub-key
superkey
surrogate key
tenkey
theoretical key
throw away the key
tipsy key
tooth key
tuning key
turnkey
turn-key
under lock and key
unkey
USB key
Walpole Cross Keys
water key
Windows key
wine key
wine-key
Winkey
witkey
Woodruff key
Related terms: key card
key chain
key change
key fob
key ring
key signature
public-key cryptography
clef
scale
Key in the Encyclopædia Britannica (11th edition, 1911)