Idioms

    power of the keys, the authority of a pope in ecclesiastical matters, vested in him as successor of St. Peter.

Origin of key

1
before 900; Middle English key(e), kay(e), Old English cǣg, cǣge; cognate with Old Frisian kei, kai

Can be confused

cay key quay

Definition for key (2 of 4)

key

2
[ kee ]
/ ki /

noun, plural keys.

a reef or low island; cay.

Origin of key

2
1690–1700; < Spanish cayo, probably < Arawak

Definition for key (3 of 4)

key

3
[ kee ]
/ ki /

noun, plural keys. Slang.

a kilogram of marijuana or a narcotic drug.

Origin of key

3
1965–70, Americanism; shortening and respelling of kilogram

Definition for key (4 of 4)

Key

[ kee ]
/ ki /

noun

Francis Scott,1780–1843, U.S. lawyer: author of The Star-Spangled Banner.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for key

British Dictionary definitions for key (1 of 3)

key

1
/ (kiː) /

noun


adjective

of great importance; cruciala key issue

verb (mainly tr)

See also key in, key up

Derived Forms

keyless, adjective

Word Origin for key

Old English cǣg; related to Old Frisian kēi, Middle Low German keie spear

British Dictionary definitions for key (2 of 3)

key

2
/ (kiː) /

noun

a variant spelling of cay

British Dictionary definitions for key (3 of 3)

Key

/ (kiː) /

noun

John (Phillip). born 1961, New Zealand politician; prime minister from 2008

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for key

key

[ kē ]

See cay.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Culture definitions for key

key

The main or central note of a piece of music (or part of a piece of music). Each key has its own scale, beginning and ending on the note that defines the octave of the next scale. The key of C-major uses a scale that starts on C and uses only the white keys of the piano. In a piece composed in the key of C, the music is likely to end on the note C, and certain combinations of notes based on C will predominate.


The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Idioms and Phrases with key

key

In addition to the idiom beginning with key

  • key up

also see:

  • in key
  • under lock and key

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.