surveillance

noun

sur·​veil·​lance sər-ˈvā-lən(t)s 

also

-ˈvāl-yən(t)s 

or

-ˈvā-ən(t)s 

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

also : supervision see also immune surveillance

Synonyms of surveillance

• stewardship
• supervision
• oversight
• management
• control
• policing
• regulation

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

The Defense Department’s budget for quadcopters is relatively small, however, according to Ryan Tseng, so Shield AI pivoted in 2021 via its acquisition of the V-BAT, a towering surveillance drone capable of flying up to 18,000 feet and for 13 hours into enemy territory. —Jessica Mathews, Fortune, 21 Dec. 2025

The cameras, run by surveillance company Flock Safety, spotted his vehicle at least 14 times starting nearly two weeks before the shooting, according to a police affidavit. —Arkansas Online, 21 Dec. 2025

Investigators connected Breham and Franklin to the shooting via surveillance footage, cellphone records and DNA testing. —Wcco Staff, CBS News, 21 Dec. 2025

While surveillance footage and the help of a social media tip led investigators to his rental car, the investigation now looks to understand the motive behind the killings. —Eryn Dion, USA Today, 20 Dec. 2025

Word History

Etymology

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

Phrases Containing surveillance

• counter-surveillance
• electronic surveillance
• immune surveillance
• immunological surveillance
• keep under surveillance

Kids Definition

surveillance

noun

sur·​veil·​lance sər-ˈvā-lən(t)s 

also -ˈvāl-yən(t)s

or -ˈvā-ən(t)s

: close watch

under surveillance

Medical Definition

surveillance

noun

sur·​veil·​lance

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