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definitions

lockdown

[lok-doun]
See more synonyms for lockdown on Thesaurus.com
noun
  1. the confining of prisoners to their cells, as following a riot or other disturbance.
  2. a security measure taken during an emergency to prevent people from leaving or entering a building: The school remains under lockdown due to police activity in the area.

Origin of lockdown

1970–75; lock1 + -down, probably extracted from nouns formed from phrasal verbs, such as crackdown, shutdown, etc.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for lockdown

isolation, solitary, lockdown

Examples from the Web for lockdown

Contemporary Examples of lockdown

British Dictionary definitions for lockdown

lockdown

noun
  1. US a security measure in which those inside a building such as a prison, school, or hospital are required to remain confined in it for a timemany schools remained under lockdown yesterday
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
Word Origin and History for lockdown
n.

also lock-down, from 1940s in various mechanical senses, from lock (v.) + down (adv.). Prison sense is by 1975, American English.

Online Etymology Dictionary, © 2010 Douglas Harper