From Longman Dictionary of Contemporary Englishsurveillancesur‧veil‧lance /səˈveɪləns $ sər-/ noun [uncountable] 1 WATCHwhen the police, army etc watch a person or place carefully because they may be connected with criminal activitiessurveillance of 24-hour surveillance of the buildingunder surveillance They were under constant close surveillance day and night. The suspects were kept under surveillance. electronic surveillance equipment2 when one country watches the military activities of another country to see what they are planning to do a surveillance mission surveillance aircraft3 when doctors, health departments etc watch an ill person or watch the development of a disease in a populationunder surveillance Diane was placed under psychiatric surveillance.
Examples from the Corpus
surveillance• These cancer surveillance programmes are now widely implemented despite not having been subjected to clinical trial.• Patients with increased oesophageal alkalinisation require careful surveillance because of their increased likelihood of developing complications.• The terrorists had been kept under constant surveillance by our officers.• Banks are installing surveillance cameras to prevent robberies.• Military intelligence maintained its surveillance of black organizational activity to determine the extent of black radicalism.• Police surveillance has prevented us contacting your sister-in-law.• It was reported that the agreement covered missile systems, light armoured vehicles and sea surveillance aircraft.• Television surveillance in public areas should help to make housing developments safer.• This patient was the only case of cancer detected by the surveillance programme.• The men had been under surveillance by customs officers for some time before their arrest.• And even this unobtrusive surveillance might be only a part of her fantasy.kept under surveillance• The suspects were kept under surveillance.Origin surveillance (1800-1900) French surveiller “to watch over”, from sur- ( → SURCHARGE) + veiller “to watch” (from Latin vigil; → VIGIL) 