Source : Webster's Revised Unabridged Dictionary (1913)

Surveillance \Sur*veil"lance\, n. [F., fr. surveiller to watch
   over; sur over + veiller to watch, L. vigilare. See {Sur-},
   and {Vigil}.]
   Oversight; watch; inspection; supervision.

         That sort of surveillance of which . . . the young have
         accused the old.                         --Sir W.
                                                  Scott.

Source : WordNet®

surveillance
     n : close observation of a person or group (usually by the
         police)