key

A key is a piece of metal that fits inside a lock and turns to open it. You might have a key ring with a house key, a car key, and maybe several more keys.

A key is typically cut from metal, although many hotels use plastic keys for their guest rooms. If you are told that your attendance is key, you know you have to go. Another meaning of key is a button or lever you press with your fingers, like a piano key or a typewriter key. A key is also an explanation, like the answer key for a test or the key to success. And when you sing in key, you have the correct pitch.

Primary Meanings of key

1.
nv
metal device shaped in such a way that when it is inserted into the appropriate lock the lock's mechanism can be rotated
provide with a key
2.
nvadj
something crucial for explaining
identify as in botany or biology, for example
serving as an essential component
3.
nv
any of 24 major or minor diatonic scales that provide the tonal framework for a piece of music
regulate the musical pitch of
4.
n
a kilogram of a narcotic drug
5.
n
a winged often one-seed indehiscent fruit as of the ash or elm or maple
6.
n
a coral reef off the southern coast of Florida
7.
n
the central building block at the top of an arch or vault
8.
n
(basketball) a space (including the foul line) in front of the basket at each end of a basketball court; usually painted a different color from the rest of the court
Full Definitions of key
1

n metal device shaped in such a way that when it is inserted into the appropriate lock the lock's mechanism can be rotated

Types:
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ignition key
a key that operates the ignition switch of an automotive engine
latchkey
key for raising or drawing back a latch or opening an outside door
master, master key, passe-partout, passkey
key that secures entrance everywhere
skeleton key
a passkey with much of the bit filed away so that it can open different locks
Type of:
device
an instrumentality invented for a particular purpose

n mechanical device used to wind another device that is driven by a spring (as a clock)

Synonyms:
winder
Types:
watch key
winder consisting of a key with a square hole; used for winding some watches
Type of:
mechanical device
mechanism consisting of a device that works on mechanical principles

n a lever (as in a keyboard) that actuates a mechanism when depressed

Types:
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backspace, backspace key, backspacer
the typewriter key used for back spacing
command key, control key
(computer science) the key on a computer keyboard that is used (in combination with some other key) to type control characters
return, return key
the key on electric typewriters or computer keyboards that causes a carriage return and a line feed
shift, shift key
the key on the typewriter keyboard that shifts from lower-case letters to upper-case letters
space bar
the bar-shaped typewriter key that introduces spaces when used
tab, tab key
the key on a typewriter or a word processor that causes a tabulation
telegraph key
key consisting of a lever that sends a telegraph signal when it is depressed and the circuit is closed
Type of:
lever
a rigid bar pivoted about a fulcrum

n a generic term for any device whose possession entitles the holder to a means of access

“a safe-deposit box usually requires two keys to open it”
Type of:
positive identification
evidence proving that you are who you say you are; evidence establishing that you are among the group of people already known to the system; recognition by the system leads to acceptance

v provide with a key

“We were keyed after the locks were changed in the building”
Type of:
furnish, provide, render, supply
give something useful or necessary to

v vandalize a car by scratching the sides with a key

“His new Mercedes was keyed last night in the parking lot”
Type of:
vandalise, vandalize
destroy wantonly, as through acts of vandalism
2

n something crucial for explaining

“the key to development is economic integration”
Type of:
explanation
thought that makes something comprehensible

n a list of answers to a test

“some students had stolen the key to the final exam”
Type of:
list, listing
a database containing an ordered array of items (names or topics)

n a list of words or phrases that explain symbols or abbreviations

Types:
key word
a word that is used as a pattern to decode an encrypted message
Type of:
list, listing
a database containing an ordered array of items (names or topics)

v identify as in botany or biology, for example

v harmonize with or adjust to

key one's actions to the voters' prevailing attitude”
Type of:
harmonise, harmonize, reconcile
bring into consonance or accord

adj serving as an essential component

Synonyms:
cardinal, central, fundamental, primal
important, of import
of great significance or value
3

n any of 24 major or minor diatonic scales that provide the tonal framework for a piece of music

Synonyms:
tonality
Antonyms:
atonalism, atonality
the absence of a key; alternative to the diatonic system
Types:
major key, major mode
a key whose harmony is based on the major scale
minor key, minor mode
a key based on the minor scale
home key, tonic key
the basic key in which a piece of music is written
Type of:
musical notation
(music) notation used by musicians

n pitch of the voice

“he spoke in a low key
Type of:
pitch
the property of sound that varies with variation in the frequency of vibration

v regulate the musical pitch of

Type of:
chord, harmonise, harmonize
bring into consonance, harmony, or accord while making music or singing
4

n a kilogram of a narcotic drug

“they were carrying two keys of heroin”
Type of:
kg, kilo, kilogram
one thousand grams; the basic unit of mass adopted under the Systeme International d'Unites
5

n a winged often one-seed indehiscent fruit as of the ash or elm or maple

Synonyms:
key fruit, samara
Type of:
achene
small dry indehiscent fruit with the seed distinct from the fruit wall
6

n a coral reef off the southern coast of Florida

Synonyms:
Florida key, cay
Type of:
coral reef
a reef consisting of coral consolidated into limestone
7

n the central building block at the top of an arch or vault

Synonyms:
headstone, keystone
Types:
coign, coigne, quoin
the keystone of an arch
Type of:
building block
a block of material used in construction work
8

n (basketball) a space (including the foul line) in front of the basket at each end of a basketball court; usually painted a different color from the rest of the court

“he hit a jump shot from the top of the key
Synonyms:
paint
Type of:
space
an area reserved for some particular purpose

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