[ 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.See also electronic surveillance.
attentive observation, as to oversee and direct someone or something: increased surveillance of patients with chronic liver disease.

Nearby words

  1. surtout,
  2. surtsey,
  3. suruga bay,
  4. surv.,
  5. surveil,
  6. surveillance society,
  7. surveillant,
  8. survey,
  9. survey course,
  10. survey.

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 formscoun·ter·sur·veil·lance, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for surveillance

British Dictionary definitions for surveillance


/ (sɜːˈveɪləns) /


close observation or supervision maintained over a person, group, etc, esp one in custody or under suspicion
Derived Formssurveillant, adjective, noun

Word Origin for surveillance

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

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

Medicine definitions for surveillance


[ sər-vāləns ]


Close observation of a person or group, especially one under suspicion.
The act of observing or the condition of being observed.
The collection, collation, analysis, and dissemination of data.
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.