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

French media reports say the museum once used its own name, Louvre, as a password for its surveillance system. —Kurt Knutsson, FOXNews.com, 9 Nov. 2025

Privacy and civil liberties advocates also warn these surveillance tools represent a grave threat and say there is not a sufficient regulatory framework in place or oversight to ensure federal agents are using new technologies in a way that protects privacy and constitutional rights. —Jude Joffe-Block, NPR, 8 Nov. 2025

That day, the pair was captured on the rental agency’s surveillance camera appearing to be wearing wigs. —Elizabeth Wolfe, CNN Money, 8 Nov. 2025

Australia is set to build a new underwater surveillance network to better monitor and defend its northern maritime approaches. —Christopher McFadden, Interesting Engineering, 8 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