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

• 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

Though the method of attack wasn’t revealed, an investigation found the hacker had obtained call and location data from the attache’s phone and surveillance video Mexico City's camera system. —Thomas Brewster, Forbes.com, 1 July 2025

Police said the crime scene remains active as detectives continue seeking witnesses, video surveillance and other evidence. —Brian Bell, The Orlando Sentinel, 28 June 2025

The Trump administration has lifted a freeze on federal funds for HIV prevention and surveillance programs, officials said, following an outcry from HIV prevention organizations, health experts and Democrats in Congress. —Susanne Rust, Los Angeles Times, 27 June 2025

Federal prosecutors argued Combs and his associates were worried about being arrested after the attack on Ventura caught on 2016 hotel surveillance cameras and sought to bribe a security guard in return for the footage. —Aaron Katersky, ABC News, 27 June 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