Meaning of KEY in English

I. ˈkē noun

( -s )

Usage: often attributive

Etymology: Middle English key, kay, keye, from Old English cǣg, cǣge, cǣga; akin to Old Frisian kēi, kāi key, Middle Low German keie, keige spear, and perhaps to Old High German kīl wedge — more at chine


a. : an instrument usually of metal so designed that it may be inserted in a lock in order to operate the bolt or catch

b. : a tool with a shaft that fits into printers' quoins and is rotated to tighten or loosen them

c. : a small metal piece with a slot in one end used to roll up a strip of metal (as on a can of sardines) or to roll up the body of a collapsible metal tube (as a tube of toothpaste)

2. : something that affords or prevents entrance, possession, or control


a. : something that serves to reveal or solve a problem, difficulty, or mystery

the key to a riddle

b. : a simplified version that accompanies something as a clue to its explanation (as an outline map, a word-for-word translation, a book containing solutions to problems) ; specifically : a list of words or phrases giving the value of symbols (as a pronunciation alphabet)

c. : an arrangement of the salient characters of a group of plants or animals or of species or genera for the purpose of determining the names and taxonomic relationships of unidentified members of a group

d. : the matter used to key an advertisement

e. : a map legend

4. keys plural : spiritual authority in a Christian religion

power of the keys

specifically : the power or jurisdiction of the presidency in the Mormon Church

5. : a tool or device used to transfer, wind, or otherwise move usually in order to secure or tighten: as


(1) : cotter pin

(2) : cotter

b. : a keystone in an arch

c. : a wedge used to make a dovetail joint

d. : a wedge between two feathers to break a stone

e. : the last board laid in a floor

f. : a tapered block driven into a recess in a scarf joint between two timbers so as to draw them more firmly together

g. : a small wooden wedge that is forced into the dovetail joint at a corner of a stretcher frame of a painting in order to tighten the canvas

h. : a wedge used to split a tenon in a mortise or the upper end of a tool handle (as a hammer or ax) for the purpose of tightening

i. : any of the metal U-shaped devices used to secure the bands or cords in position in a bookbinder's sewing press

j. : a strip of wood inserted in a timber across the grain to prevent casting

k. : a small usually metal parallel-sided piece that is flat or tapered on top and that is used for securing a part (as a pulley, crank, or hub)


a. : one of the levers (as a digital or pedal) of a keyboard musical instrument that actuates the mechanism and produces the tones

b. : a lever by which a vent is opened or closed in the side of a woodwind instrument (as a clarinet or bassoon) or a valve or piston is controlled in a brass instrument (as a French horn or trumpet)

c. : a depressible digital that serves as one unit of a keyboard and that works usually by lever action to set in motion a character (as in a typewriter) or an escapement (as in some typesetting machines)

d. : keybutton

7. : samara


a. : a leading, prominent, or critical individual or principle

a key actor

the key features of a new car

b. : a component of a liquid mixture that is being separated by fractional distillation

the least volatile of these components is the heavy key and the most volatile is the light key — E.G.Scheibel


[translation of Medieval Latin clavis ]

a. obsolete : the lowest note or keynote of a scale


(1) : a system of seven tones based on their relationship to a keynote or tonic ; specifically : the tonality of a scale

(2) : the total harmonic and melodic relations of such a system


a. : characteristic style, tone, or intensity of thought, feeling, or action

b. : the tone or pitch of a voice

speaking in a plaintive key

c. : the pervading tone and intensity of color (as in a painting)

d. : the predominant tone of a photograph with respect to its lightness or darkness — compare high-key , low-key

11. : a decoration or charm resembling a key



(1) : plastering forced between laths to hold the rest in place

(2) : the hold that plaster has on a wall

(3) : the roughness of a wall that causes plaster to adhere to it

b. : a hollow in a brick or tile to hold mortar

c. : the rough surface on the wrong side of a veneer to hold the glue


a. : a metallic lever for rapidly and easily opening and closing the circuit of telegraphic-station equipment

b. : a small switch for opening or closing an electric circuit

14. : a projecting portion used to prevent movement at a construction joint (as of a floor, wall, pavement, footing, dam) into the adjacent section

15. or keymove ˈ ̷ ̷| ̷ ̷ : the first move in the solution of a chess problem or combination


a. : the control of a cryptographic process (as a code book, grille, cipher alphabet, or set of alphabets)

b. : the enciphering or deciphering instructions for a cryptogram: as

(1) : the settings of a ciphering machine

(2) : the column sequence of a transposition

(3) : keying sequence

(4) : key word

(5) : key letter

(6) : an element in a keying sequence — see periodic key , period key , running key , specific key , vigene re cipher

17. : keyhole 4

II. verb

( -ed/-ing/-s )

Etymology: Middle English keyen, from key, kay, keye, n.

transitive verb

1. : to lock with or as if with a key : fasten: as

a. : to secure by a key (as a hammerhead to a handle, a pulley on a shaft, plaster to lathing)

b. : to finish off (an arch) by inserting a keystone

c. : to expand and tighten (as a canvas stretcher on a painting) with keys


a. : to fix or determine the musical key of

b. : to regulate the musical pitch of

key the strings

c. : to control (a process) in cryptography

in keyed columnar transposition the column sequence is controlled by a key word

— compare keying sequence

3. : to apply color to (as a painting) in a particular key

4. : harmonize , attune

remarks keyed to a situation

5. : to transmit by means of a telegraph key

6. : to identify (a biological specimen) by means of a key

7. : to insert in (an advertisement) some direction or other matter intended to identify answers : apply a symbol to (an advertisement) by means of which identification is effected

8. : to produce or cause nervous tension in — used with up

keyed up over the prospect of an operation

9. : keyboard

intransitive verb

: to use a key: as

a. : to permit of identification by means of a key — often used with out

the specimen keys out to a genus of common starfish

b. : to operate a telegraph key



variant of quay

IV. noun

also kay like cay I

( -s )

Etymology: modification (influenced by key ) (III) of Spanish cayo, from Lucayo cayo

: a low island or reef ; specifically : one of the coral islets off the southern coast of Florida

V. verb

transitive verb

: to be essential to : play the most important part in

defense keyed the victory

intransitive verb

1. : 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

2. : keyboard

VI. ˈkē noun

( -s )

Etymology: by shortening & alteration of kilo

slang : a kilogram especially of marijuana or heroin

Webster's New International English Dictionary.      Новый международный словарь английского языка Webster.