surveillance

ser-VAY-lunss /sərˈveɪləns/
nounC1GREIELTSTOEFLUPSC
formal

Close observation of a suspect, group, or location, especially by police or intelligence forces.

Implies sustained, organized, and often covert monitoring over time.

The story behind the word. Surveillance entered English from French, combining 'sur-' (over) and 'veiller' (to watch, from Latin 'vigilare'). Literally, it means watching over someone from above or afar.

Word relationships

  • observation: Observation is general, while surveillance is targeted, systematic monitoring.
  • reconnaissance: Reconnaissance is military scouting prior to tactical operations.
  • neglect: Failing to watch or oversee an area or individual.

Commonly confused with

  • patrol: Patrolling is visible physical moving around; surveillance is often covert and stationary observation.

Word family

  • surveil (verb): To keep an individual or place under surveillance
  • surveillant (noun): A person who maintains surveillance

Collocations

  • under surveillance
  • surveillance camera
  • electronic surveillance
  • conduct surveillance

Idioms & expressions

  • keep under surveillance

Example sentences

  • "The task force placed the warehouse under continuous surveillance for three weeks." Police investigation
  • "High-definition surveillance cameras were installed throughout the international airport." Security technology

Memory hook

SURVEILLANCE is SURVEYING from above with VIGILANCE. Close, continuous watching.

When not to use

Do not use for a quick glance or casual observation.

Fun facts

  • The verb 'surveil' was back-formed in the 1960s, long after the noun 'surveillance' entered English in 1802.

Related words

patrol, detective, warrant

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