Definition of surveillance
: close watch kept over someone or something (as by a detective); also : supervision
Examples of surveillance in a sentence
government surveillance of suspected terrorists
The bank robbery was recorded by surveillance video cameras.
Origin and Etymology of surveillance
French, from surveiller to watch over, from sur- + veiller to watch, from Old French veillier, from Latin vigilare, from vigil watchful — more at vigil
First Known Use: 1802
SURVEILLANCE Defined for English Language Learners
Definition of surveillance for English Language Learners
: the act of carefully watching someone or something especially in order to prevent or detect a crime
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