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

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.

Recent Examples on the Web

Trump nearly bombed Iran last month after Tehran shot down a U.S. military surveillance drone. Deirdre Shesgreen, USA TODAY, "House votes to end US role in Yemen, poised to block Trump from launching Iran strike," 11 July 2019 After his parents defected to the North, the younger Mr. Choe, who was left behind in the South, lived under surveillance during the military dictatorship. Choe Sang-hun, New York Times, "South Korean Defects to the North, Following in His Parents’ Footsteps," 8 July 2019 After his parents defected to the North, the younger Choe, who was left behind in the South, lived under surveillance during the military dictatorship. Choe Sang-hun,, "South Korean defects to the North, following in his parents’ footsteps," 8 July 2019 Those who do get out are placed under strict surveillance. Ryan Faircloth, Twin Cities, "The life sentence they got for murder came with a chance at parole. Will these Minnesota ‘lifers’ get out?," 29 June 2019 Harris was armed with a gun and had been under surveillance by Phoenix police during a string of robberies in which he was involved that night. azcentral, "Phoenix officers who killed fleeing robbery suspect have 6 police shootings between them, records show," 26 June 2019 Among the 16 contestants vying for a $500,000 prize while living together under around-the-clock surveillance are a therapist, a petroleum engineer, a Broadway performer, and a wine safari guide. Ew Staff,, "What to Watch on Tuesday: Big Brother turns 21, plus Meghan Trainor on Songland," 25 June 2019 Television cameras watch the corridor and the comers, look into the barracks and the exercise yards; the entire camp is under constant electronic surveillance. Earl Shorris, Harper's magazine, "El Corralón," 24 June 2019 Authorities say there was never any danger to the public because Alowemer was under FBI surveillance for months. NBC News, "Syrian refugee charged with plotting to bomb Pennsylvania church," 19 June 2019

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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Dictionary Entries near surveillance

Suruga Bay







Statistics for surveillance

Last Updated

17 Jul 2019

Look-up Popularity

Time Traveler for surveillance

The first known use of surveillance was in 1802

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More Definitions for surveillance



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).


appealing forcibly to the mind or reason

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