key1

noun (plural keys)

• 1a small piece of shaped metal with incisions cut to fit the wards of a particular lock, and that is inserted into a lock and turned to open or close it.
• a small, shaped metal implement for operating a switch in the form of a lock, especially one operating the ignition of a motor vehicle.
• short for key card.
• an instrument for grasping and turning a screw, peg, or nut, especially one for winding a clock or turning a valve.
• a pin, bolt, or wedge inserted between other pieces, or fitting into a hole or space designed for it, so as to lock parts together.

• 2each of several buttons on a panel for operating a computer, typewriter, or telephone.
• a lever depressed by the finger in playing an instrument such as the organ, piano, flute, or concertina.
• a lever operating a mechanical device for making or breaking an electric circuit, for example, in telegraphy.

• 3a thing that provides a means of gaining access to or understanding something:the key to Jack’s behavior may lie submerged in his unhappy past
• an explanatory list of symbols used in a map, table, etc..
• a set of answers to exercises or problems.
• a word or system for solving a cipher or code.
• the first move in the solution of a chess problem.
• Computing a field in a record that is used to identify that record uniquely.

• 4 Music a group of notes based on a particular note and comprising a scale, regarded as forming the tonal basis of a piece or passage of music:the key of E minor
• the tone or pitch of someone’s voice:his voice had changed to a lower key
• the prevailing tone or tenor of a piece of writing, situation, etc.:it was like the sixties all over again, in a new, more austerely intellectual key
• the prevailing range of tones or intensities in a painting:these mauves, lime greens, and saffron yellows recall the high key of El Greco’s palette

• 5the dry winged fruit of an ash, maple, or sycamore maple, typically growing in bunches; a samara.

• 6British the part of a first coat of wall plaster that passes between the laths and so secures the rest.
• [in singular] the roughness of a surface, helping the adhesion of plaster or other material.

• 7 Basketball the keyhole-shaped area marked on the court near each basket, comprising the free-throw circle and the foul line.

adjective

• of paramount or crucial importance:she became a key figure in the suffragette movement

verb (keys, keying, keyed /kēd/)

• 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 considerable disruption after keying into a vital database

• 2 (usually be keyed) fasten (something) in position with a pin, wedge, or bolt:the coils may be keyed into the slots by fiber wedges

• 3British roughen (a surface) to help the adhesion of plaster or other material.

• 4word (an advertisement in a particular periodical), typically by varying the form of the address given, so as to identify the publication generating particular responses.

• 5 informal be the crucial factor in achieving:Ewing keyed a 73-35 advantage on the boards with twenty rebounds

• 6vandalize a car by scraping the paint from it with a key:somebody could key your car and not get punished