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

Example Sentences

government surveillance of suspected terrorists The bank robbery was recorded by surveillance video cameras.
Recent Examples on the Web According to Reuters, online images show hundreds of Foxconn workers protesting with surveillance cameras and windows smashed by men with sticks. José Adorno, BGR, 23 Nov. 2022 The video appears to be from the detention center’s surveillance system and was obtained through a separate legal proceeding in North Carolina involving Hobbs. Alta Spells, CNN, 16 Nov. 2022 Friends on the scene that day said the couple’s home was equipped with a video surveillance system, but police have not said whether that yielded any clues. Carol Robinson |, al, 3 Nov. 2022 So on Santa Cruz Island, the Nature Conservancy has been experimenting with a surveillance system to learn whether rats have landed, using a network of wildlife camera traps and the same AI technique that recognizes human faces in photographs. WIRED, 24 Oct. 2022 The strike disabled computers linked to 126 street cameras in a video surveillance system monitoring public spaces across Washington, D.C., including along the presidential parade route. Renee Dudley, ProPublica, 22 Oct. 2022 Health experts also hope Americans continue to take precautions against COVID-19 even though its surveillance system shifts to one that mirrors how the flu is tracked. Adrianna Rodriguez, USA TODAY, 7 Oct. 2022 In constructing a surveillance system of breathtaking scope and intrusiveness, our government also sharply eroded individual privacy. Reuters, NBC News, 26 Sep. 2022 While investigating this case, police recovered one firearm and found the bar does not have an operational surveillance system, Spagnolo said. Mike Mavredakis, Hartford Courant, 8 Sep. 2022 See More

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.

Word History


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

First Known Use

1802, in the meaning defined above

Time Traveler
The first known use of surveillance was in 1802

Dictionary Entries Near surveillance

Cite this Entry

“Surveillance.” Dictionary, Merriam-Webster, Accessed 4 Dec. 2022.

Kids Definition



sur·​veil·​lance sər-ˈvā-lən(t)s How to pronounce surveillance (audio)
 also  -ˈvāl-yən(t)s,
 or  -ˈvā-ən(t)s
: close watch
under surveillance

Medical Definition



sər-ˈvā-lən(t)s also -ˈvāl-yən(t)s or -ˈvā-ən(t)s
: close and continuous observation or testing
serological surveillance
see immune surveillance

More from Merriam-Webster on surveillance

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