C1nounformal10K+

Surveillance

UK /["/sɜːˈveɪləns/"]/US /["/sɜːrˈveɪləns/"]/

Definition

the act of carefully watching a person suspected of a crime or a place where a crime may be committed

In simple words: Watching someone or something carefully, often to find out more information.

Examples

  • The police are keeping the suspects **under** constant **surveillance**.
  • **surveillance cameras/equipment**
  • The suspects are under police surveillance.
  • The images were covertly captured on surveillance tape.

Usage notes

Used mainly in formal contexts such as law enforcement, security, and privacy discussions. Not appropriate in casual conversation. Can imply a sense of monitoring or intrusiveness.

Grammar pattern

surveillance + object

Memory hint

Sounds like 'serve a lance' — imagine serving someone while watching them closely.

Collocations

  • close
  • constant
  • regular
  • be under
  • keep somebody/​something under
  • place somebody/​something under
  • camera
  • device
  • equipment

Synonyms

  • observation

Antonyms

  • ignorance
  • negligence
  • carelessness

Common mistakes

  • Confused with 'surveil' (verb) and 'surveillance' (noun)
  • Mispronunciation, often as 'sur-veal-lance' instead of 'sur-veil-lance'
  • Overusing in informal settings where more casual terms could fit