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

She was linked to the fire through cell phone records, credit card records and surveillance video, according to the plea agreement and the federal indictment. —Landon Mion, FOXNews.com, 7 Sep. 2025

In addition to the surveillance footage, O’Dell was also linked to the arson through her cell phone and credit card records, the release stated, citing the plea agreement and federal indictment. —Bailey Richards, PEOPLE, 7 Sep. 2025

The sheriff's office said investigators are reviewing surveillance footage from the bar. —Thao Nguyen, USA Today, 7 Sep. 2025

On Friday, Israel hit Mushtaha Tower, a local landmark that housed dozens of families, saying Hamas militants had used it for surveillance. —Wafaa Shurafa, Arkansas Online, 7 Sep. 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