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

The incident happened on September 25, according to the surveillance video timestamp. —Pilar Arias, FOXNews.com, 5 Oct. 2025

Detectives, according to police officials, are interviewing witnesses and combing through surveillance video in an effort to identify suspects. —Bill Hutchinson, ABC News, 5 Oct. 2025

Police recovered three bullet casings at the crime scene as well as surveillance footage that showed a man in a white Chevrolet Silverado entering the clinic on the day Tokuhara was murdered. —Emily Blackwood, PEOPLE, 4 Oct. 2025

Combs also apologized to abuse victims around the world who may have been triggered by the surveillance footage of him assaulting Ventura. —Nicki Brown, CNN Money, 4 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