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[ser-vey-luh ns, -veyl-yuh ns] /sərˈveɪ ləns, -ˈveɪl yəns/
a watch kept over a person, group, etc., especially over a suspect, prisoner, or the like:
The suspects were under police surveillance.
continuous observation of a place, person, group, or ongoing activity in order to gather information:
video cameras used for covert surveillance.
attentive observation, as to oversee and direct someone or something:
increased surveillance of patients with chronic liver disease.
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
Related forms
countersurveillance, noun Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
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Examples from the Web for surveillance
Contemporary Examples
Historical Examples
  • It was only during a pause for breath that he became aware of the surveillance.

    The Fortune Hunter Louis Joseph Vance
  • Was it the consciousness of this surveillance that made every one keep the house?

    A Day's Ride Charles James Lever
  • It was the citoyen Beauvisage, of the Committee of surveillance.

    The Gods are Athirst Anatole France
  • After awhile, he became conscious that he was under a sort of surveillance.

    White Lies Charles Reade
  • And then, released from surveillance, exhausted in mind and body—he fell again.

    The Lowest Rung

    Mary Cholmondeley
British Dictionary definitions for surveillance


close observation or supervision maintained over a person, group, etc, esp one in custody or under suspicion
Derived Forms
surveillant, adjective, noun
Word Origin
C19: from French, from surveiller to watch over, from sur-1 + veiller to keep watch (from Latin vigilāre; see vigil)
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
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Word Origin and History for surveillance

1802, from French surveillance "oversight, supervision, a watch," noun of action from surveiller "oversee, watch," from sur- "over" + veiller "to watch," from Latin vigilare, from vigil "watchful" (see vigil). Seemingly a word of the Terror in France.

Online Etymology Dictionary, © 2010 Douglas Harper
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surveillance in Medicine

surveillance sur·veil·lance (sər-vā'ləns)

  1. Close observation of a person or group, especially one under suspicion.

  2. The act of observing or the condition of being observed.

  3. The collection, collation, analysis, and dissemination of data.

  4. A type of observational study that involves continuous monitoring of disease occurrence within a population.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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