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

Iran’s crackdown on nationwide protests continued Sunday, with reports of mass killings as demonstrations spread across the country amid warnings of drone surveillance. —Emma Bussey, FOXNews.com, 12 Jan. 2026

Police released a video asking for help before arresting McKee in Rockford, Illinois, linking him to a car seen on surveillance video around the murder scene. —Sara MacHi, CBS News, 12 Jan. 2026

Police announced McKee's arrest on Saturday after he was linked to a car seen on surveillance footage in the neighborhood, according to court documents. —Emily Shapiro, ABC News, 12 Jan. 2026

Drone use is increasing in Africa across various sectors, including by the military for surveillance and warfare like in Sudan, but also for social services. —Alexander Onukwue, semafor.com, 12 Jan. 2026

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