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

Flock Safety also supplies the most surveillance cameras to continuously record details about vehicles driven across North Carolina, The News & Observer reported last year. —Joe Marusak, Charlotte Observer, 13 Oct. 2025

There are multiple angles of surveillance footage which capture the events that occurred. —Devon Henderson, New York Times, 12 Oct. 2025

Mariângela Batista Galvão Simão, Brazil’s secretary of health and environmental surveillance, oversaw the arrival of the first batch of fomepizole at São Paulo’s Guarulhos International Airport. —Alessandra Freitas, CNN Money, 12 Oct. 2025

The White House border czar, Tom Homan, was recorded on an FBI surveillance tape in September 2024 accepting $50,000 in cash. —ABC News, 12 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