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

Also important is the education around how the surveillance cameras and the data are used against our civil liberties. —Michael James Rocha, San Diego Union-Tribune, 30 Nov. 2025

The lodge has surveillance cameras, but police have yet to receive or review that footage as the lodge works to compile all video before handing it over. —Peter Aitken, MSNBC Newsweek, 29 Nov. 2025

Public health experts expect the new WHO code to dramatically improve surveillance and help physicians spot trends, especially as legalization spreads and high-potency products proliferate. —Deirdre Bardolf, FOXNews.com, 29 Nov. 2025

Studies required after vaccines are approved and surveillance systems, including the Vaccine Adverse Event Reporting System (VAERS), also flag potential safety issues once vaccines are in use. —Rob Stein, NPR, 29 Nov. 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