Idioms

Origin of lock

1
before 900; Middle English; Old English loc fastening, bar; cognate with Middle Low German lok, Old High German loh, Old Norse lok a cover, lid, Gothic -luk in usluk opening; akin to Old English lūcan to shut

Related forms

lock·less, adjectiveself-lock·ing, adjectivewell-locked, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for under lock and key (1 of 2)

lock

1
/ (lɒk) /

noun

verb

Derived Forms

lockable, adjective

Word Origin for lock

Old English loc; related to Old Norse lok

British Dictionary definitions for under lock and key (2 of 2)

lock

2
/ (lɒk) /

noun

a strand, curl, or cluster of hair
a tuft or wisp of wool, cotton, etc
(plural) mainly literary hair, esp when curly or fine

Word Origin for lock

Old English loc; related to Old Frisian lok, Old Norse lokkr lock of wool
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

Idioms and Phrases with under lock and key (1 of 2)

under lock and key


Securely locked up, as in He keeps the wine under lock and key. [First half of 1500s]

Idioms and Phrases with under lock and key (2 of 2)

lock


In addition to the idioms beginning with lock

  • lock horns
  • lock in
  • lock out
  • lock the barn door after the horse has bolted
  • lock up

also see:

  • 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.