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

Or they could be persuaded that financial surveillance of businesses for transactions over $200 is necessary to prevent criminals from moving money. —Agustina Vergara Cid, Oc Register, 13 July 2025

Detectives are reviewing surveillance footage and seeking witnesses to the collission, Orland Park police said. —Daily Southtown, Chicago Tribune, 13 July 2025

The probe will include interviews of all responding officers and witnesses and a review of all video of the incident, including clips posted to social media as well as public and private surveillance footage. —Matthew Medsger, Boston Herald, 13 July 2025

Angulo, his businesses and his associates were under surveillance for nearly five months, from March through July 2025, according to federal court records. —Jimmy Jenkins, AZCentral.com, 12 July 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