From Middle Englishkeye, kaye, keiȝe, from Old Englishcǣġ, cǣġe, cǣga(“key, solution, experiment”) (whence also Scotskey and kay(“key”)), of uncertain origin. Related to Old Englishcǣggian(“to lock, shut”). The only sure cognates are Saterland Frisian Koai(“key”), West Frisiankaai(“key”), and North Frisiankay(“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 Germankāk(“whipping post, pillory”), and perhaps to Middle Dutchkeige(“javelin, spear”) and Middle Low Germankeie, 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."
An object designed to open and close a lock.
An object designed to fit between two other objects (such as a shaft and a wheel) in a mechanism and maintain their relative orientation.
A crucial step or requirement.
Those who are accustomed to reason have got the true key of books.
who keeps the keys of all the creeds
A guide explaining the symbols or terminology of a map or chart; a legend.
A guide to the correct answers of a worksheet or test.
(computing) One of several small, usually square buttons on a typewriter or computer keyboard, mostly corresponding to text characters.
In musical instruments, one of the valve levers used to select notes, such as a lever opening a hole on a woodwind.
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.
1881, R.L. Stevenson, Virginibus Puerisque:
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.
The lowest note of a scale; keynote.
In musical theory, the total melodic and harmonic relations, which exist between the tones of an ideal scale, major or minor; tonality.
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.
In musical notation, a sign at the head of a staff indicating the musical key.
(figuratively) The general pitch or tone of a sentence or utterance.
?, William Cowper, Conversation
You fall at once into a lower key.
(advertising) A modification of an advertisement so as to target a particular group or demographic.
1998, Mail Order Success Secrets
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.
(botany) An indehiscent, one-seeded fruit furnished with a wing, such as the fruit of the ash and maple; a samara.
(historical) A manual electrical switching device primarily used for the transmission of Morse code.
(cryptography) A piece of information (e.g. a passphrase) used to encode or decode a message or messages.
(Internet) A password restricting access to an IRC channel.
2000, "Robert Erdec", Re: Help; mIRC32; unable to resolve server arnes.si (on newsgroup alt.irc.mirc)
if you know someone who is in the channel, you can query them and ask for the key.
(databases) In a relational database, a field used as an index into another table (not necessarily unique).
(computing) A value that uniquely identifies an entry in a container.
(basketball) 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.
(biology) A series of logically organized groups of discriminating information which aims to allow the user to correctly identify a taxon.
(architecture) A piece of wood used as a wedge.
(architecture) The last board of a floor when laid down.
(masonry) A keystone.
That part of the plastering which is forced through between the laths and holds the rest in place.
(rail transport) A wooden support for a rail on the bullhead rail system.
The degree of roughness, or retention ability of a surface to have applied a liquid such as paint, or glue.
(cartomancy) The thirty-third card of the Lenormand deck.
(print and film) The black ink layer, especially in relation to the three color layers of cyan, magenta, and yellow. See also CMYK.
(computer graphics, television) A color to be masked or made transparent.
2004, Mark Schmidt, Simon Robinson, Microsoft Visual C# .NET 2003 Developer's Cookbook (page 195)
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.
key on Wikipedia.Wikipedia
Key in the Encyclopædia Britannica (11th edition, 1911)
key (comparativemore key, superlativemost key)
Indispensable, supremely important.
He is the key player on his soccer team.
2007, Mark H. Moss, Shopping as an Entertainment Experience (page 46)
Lukas intimates that one of Disney's key attractions was "Main Street USA,” which "mimicked a downtown business district just as Southdale" had done.
She makes several key points.
key (third-person singular simple presentkeys, present participlekeying, simple past and past participlekeyed)
To fit (a lock) with a key.
To fit (pieces of a mechanical assembly) with a key to maintain the orientation between them.
To mark or indicate with a symbol indicating membership in a class.
Talk about similarities between the words and write them below to the left of the anchor, keying them with a plus sign (+). Talk about the characteristics that set the words apart and list them below the box to the right, keying them with a tilde sign (~).
2007, Stephen Blake Mettee, Michelle Doland, and Doris Hall, compilers, The American Directory of Writer's Guidelines, 6th ("2007–2008") edition, →ISBN, page 757,
Indicate the comparative value of each heading by keying it with a number in pencil, in the left margin, as follows:[…]
(telegraphy and radio telegraphy) To depress (a telegraph key).
(radio) To operate (the transmitter switch of a two-way radio).
(computing) (more usuallyto key in) To enter (information) by typing on a keyboard or keypad.
Our instructor told us to key in our user IDs.
(colloquial) To vandalize (a car, etc.) by scratching with an implement such as a key.
He keyed the car that had taken his parking spot.
To link (as one might do with a key or legend).
1960, Richard L. Masland, "Classification of the Epilepsies", in Epilepsia, volume 1, page 516,
The American Heart Association has prepared their own guide to classification and, keying it with the Standard Nomenclature of Diseases, have done much to encourage a concise yet complete diagnosis.
(intransitive, biology, chiefly taxonomy) To be identified as a certain taxon when using a key.
(advertising, transitive) To modify (an advertisement) so as to target a particular group or demographic.
1936, John Freeman Pyle, Marketing Principles, Organization and Policies (page 711)
Keying advertisements and counting the number of inquiries received or the number of coupons returned to indicate the "pulling power" of a particular piece of copy or the coverage of a particular advertising medium.
1998, Mail Order Success Secrets
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. Why? Because you're using an extra word or two to key the ad.
To attune to; to set at; to pitch.
To fasten or secure firmly; to fasten or tighten with keys or wedges.
Variant of cay, from Spanishcayo, from Taínocayo(“small island”)
One of a string of small islands.
the Florida Keys
Alternative form of quay.
Abbreviating kilogram, via kilo.
(slang)Clipping of kilogram (especially of a recreational drug)
2010, David J. Silas, Da Block (page 41)
So starting with ten keys of cocaine and two keys of heroin, Derrick put his plan in motion. Soon every major drug dealer and gang chief from Chicago Avenue to Evanston was in his pocket.
(This etymology is missing or incomplete. Please add to it, or discuss it at the Etymology scriptorium.)