# surveillance

Pronunciation: US say "sur-VAY-luhns" /sɚˈveɪ.ləns/; UK say "suh-VAY-luhns" /səˈveɪ.ləns/

## Noun

1. Close observation of an individual or group, especially someone under suspicion.
   - Simple: Watching a person or group closely, usually because they are suspected of something.
   - _The detective placed the apartment under round-the-clock surveillance._
   - _Constant surveillance of the suspect eventually revealed his contacts._
2. The use of sight, listening, cameras, electronic equipment, or other means to observe people and places systematically.
   - Simple: Watching places and people closely using cameras, listening devices, and other tools.
   - _Government agents maintained surveillance on the embassy for months._
   - _Electronic surveillance intercepted the group's encrypted messages._
3. Sustained observation of people or places as a way for police to collect evidence about actual or suspected crimes.
   - Simple: Watching people or places over time so police can collect proof about a crime.
   - _Detectives kept the suspect under surveillance to document his meetings with the dealer._
   - _The court ruled that the surveillance had been conducted without a proper warrant._
4. Continuous monitoring of how often a disease occurs within a population.
   - Simple: Keeping a constant watch on how often a disease appears in a population.
   - _Public health surveillance detected a sudden rise in measles cases._
   - _Continuous surveillance of mosquito populations warned officials of a coming malaria season._

## Origin

A borrowing from French surveillance ('a watching over, supervision'), from surveiller ('to watch, oversee'), formed from sur- ('over') plus veiller ('to watch'). This traces back through Old French veillier ('to stay awake') to Latin vigilāre ('to be watchful').

Source: DictionaryAI, https://dictionaryai.com/define/surveillance (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).