sur·​veil·​lance | \sər-ˈvā-lən(t)s also -ˈvāl-yən(t)s or -ˈvā-ən(t)s \

Definition of surveillance 

: close watch kept over someone or something (as by a detective) also : supervision

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Examples of surveillance in a Sentence

government surveillance of suspected terrorists The bank robbery was recorded by surveillance video cameras.

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Left behind are lawsuits from angry investors and Canadian employees who are wondering whether their work could be used to help China’s growing domestic surveillance state. Dan Levin, New York Times, "A Tech Guru Captivated Canada. Then He Fled to China.," 10 July 2018 The city’s surveillance system at the pool, which was supposed to alert dispatchers that someone had climbed the fence, was not working. Christine Dempsey,, "Hartford PD: Six Days After Boy's Drowning, Man Falsely Reports Another," 10 July 2018 In an exchange captured by the motel’s video-surveillance system, Arancio told the man, identified as Dayevion Royalston, that they were being recorded, according to the charges. Sara Jean Green, The Seattle Times, "Charges detail fatal shooting, robbery of SeaTac motel clerk," 26 June 2018 This tool is now powering the Chinese surveillance state. Yoko Kubota, WSJ, "A Chip in the Windshield: China’s Surveillance State Will Soon Track Cars," 13 June 2018 Hughes was involved in classified planning and analysis of NATO's control, command and communications surveillance systems during the Cold War. CBS News, "Neighbors stunned after "pleasant" man revealed to be long-missing Air Force officer," 12 June 2018 The new version adds contemporary touches to the narrative: the surveillance state, hacktivism, post-9/11 sociopolitical psychology and, of course, Tinder. Robert Lloyd,, "With ‘Condor,’ the classic Robert Redford thriller gets a TV reboot," 4 June 2018 The researchers showed how the technique could stop some video-surveillance systems from recording live streams. Dan Goodin, Ars Technica, "Sonic and ultrasonic attacks damage hard drives and crash OSes," 30 May 2018 Some larger nations -- such as the United Kingdom and Germany -- did not partake in the study but have their own surveillance systems to track overweight and obesity prevalence in children. Mark Lieber, CNN, "Childhood obesity is high in home of Mediterranean diet," 29 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'surveillance.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of surveillance

1802, in the meaning defined above

History and Etymology for surveillance

French, from surveiller to watch over, from sur- + veiller to watch, from Old French veillier, from Latin vigilare, from vigil watchful — more at vigil

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Last Updated

9 Oct 2018

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Time Traveler for surveillance

The first known use of surveillance was in 1802

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English Language Learners Definition of surveillance

: the act of carefully watching someone or something especially in order to prevent or detect a crime


sur·​veil·​lance | \sər-ˈvā-lən(t)s also -ˈvāl-yən(t)s or -ˈvā-ən(t)s\

Medical Definition of surveillance 

: close and continuous observation or testing serological surveillance — see immunological surveillance

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Comments on surveillance

What made you want to look up surveillance? Please tell us where you read or heard it (including the quote, if possible).


to clear from alleged fault or guilt

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