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Synonyms

surveillance

American  
[ser-vey-luhns, -veyl-yuhns] / sərˈveɪ ləns, -ˈveɪl yəns /

noun

  1. a watch kept over a person, group, etc., especially over a suspect, prisoner, or the like.

    The suspects were under police surveillance.

  2. continuous observation of a place, person, group, or ongoing activity in order to gather information.

    video cameras used for covert surveillance.

  3. attentive observation, as to oversee and direct someone or something.

    increased surveillance of patients with chronic liver disease.


surveillance British  
/ sɜːˈveɪləns /

noun

  1. close observation or supervision maintained over a person, group, etc, esp one in custody or under suspicion

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Etymology

Origin of surveillance

1790–1800; < French, equivalent to surveill ( er ) to watch over ( sur- sur- 1 + veiller < Latin vigilāre to watch; see vigil) + -ance -ance

Explanation

Many times, a person suspected of something illegal by the authorities is placed under surveillance, meaning he or she is closely watched to see if their suspicions are well-founded. If you break down the word surveillance you get the prefix sur, from the French word for "over" and the root veiller, meaning "to watch." All of which is a roundabout way of saying that if you are under surveillance, you are being closely watched — usually by the authorities, and usually not for a good reason! Those surveillance cameras in banks and stores are put there in the hopes of both preventing crimes and recognizing criminals after a crime has been committed.

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

O’Neill was also managing director of Mithril Capital, which provides funds to Thiel’s surveillance giant Palantir Technologies.

From Salon • May 7, 2026

There have been 890 laboratory-confirmed cases of hantavirus disease reported in the United States since surveillance began in 1993, according to the most recent data from the U.S.

From Los Angeles Times • May 5, 2026

It said a recent online survey found 28% of users have AI person and package detection, and 39% want facial recognition, despite concerns about surveillance and access to footage.

From The Wall Street Journal • May 5, 2026

Read more: Did JetBlue just admit to surveillance pricing?

From MarketWatch • May 4, 2026

The Bureau had kept surveillance videotapes of comings and goings into the Soviet embassy, filmed from a secret location across the street.

From "Spies: The Secret Showdown Between America and Russia" by Marc Favreau