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

Several intelligence gathering assets may also have been diverted from surveillance operations in Eastern Europe to the Caribbean, flight data suggests. —Natasha Bertrand, CNN Money, 19 Oct. 2025

Deputies working in the area put it under surveillance until San Diego police arrived and made an arrest. —Paul Sisson, San Diego Union-Tribune, 19 Oct. 2025

The film, which is based on real, infamous art heists of the decade, will leave audiences yearning for a simpler time, before the era of electronic mass surveillance, through its historically-accurate costuming, set design, visual affects, lighting and jazzy score. —Haadiza Ogwude, Cincinnati Enquirer, 17 Oct. 2025

However, the report concluded that the school had taken extensive corrective actions, such as increasing surveillance video placement, revising reporting protocols and enhancing staff training. —Sarah Rumpf-Whitten, FOXNews.com, 17 Oct. 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