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

• care
• charge
• guidance
• headship
• oversight
• regulation
• stewardship
• superintendence
• superintendency
• supervision

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

Detectives reviewed surveillance footage that shows the teen killer, who wore a ski mask and whose name is being withheld due to his age, lift his shirt during the showdown and shove his hands into his waistbands to show Jimenez he was armed, prosecutors say. —Colin Mixson, New York Daily News, 2 May 2025

Detectives with the state police Eastern District Major Crime Squad took over the investigation into both robberies and confirmed through the surveillance footage at the banks that the same individual was responsible. —Justin Muszynski, Hartford Courant, 2 May 2025

In surveillance camera footage from the same day as the Pomona raid, the 59-year-old from Guerrero, Mexico, is seen arriving at the Pomona barbershop he’s owned for more than two decades, getting out of his car to open the gate, and being blocked in by two vehicles. —Stephanie Elam, CNN Money, 2 May 2025

China also sells surveillance and censorship technology to other states and teaches them to use it. —Jill Goldenziel, Forbes.com, 1 May 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