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

The new case was found through routine National Milk Testing Strategy testing, rather than surveillance that is required before moving cattle across state lines, according to the USDA. —Hope Karnopp, jsonline.com, 14 Dec. 2025

These were widely vandalized by haters who scrawled messages denouncing Friend as a surveillance device and blasting the rise of AI overall. —Miles Klee, Rolling Stone, 14 Dec. 2025

About 20 minutes before the shooting, new surveillance video shows the suspect pull a gun on a man in the elevator of an apartment building about 10 blocks north. —Ali Bauman, CBS News, 13 Dec. 2025

In 2017, Trump’s first-term document had criticized China for its authoritarianism, mass surveillance, and push to create a new world order alongside Russia. —Jessie Yeung, CNN Money, 12 Dec. 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