adjective
- watching carefully; keeping under observation
Usage: formal
noun
- a person who watches or keeps under surveillance
Usage: formal
Examples
- The surveillant cameras recorded every movement in the building.
- Security guards remained surveillant throughout the night shift.
- The surveillant noticed suspicious activity near the entrance.
- Police assigned a surveillant to monitor the suspect’s activities.
- The surveillant equipment helped solve the case.
- She worked as a surveillant for the private investigation firm.