What is the word that describes the situation in which one is being watched, but cannot see the observer. As though the watcher resides in a tower, while the subject walks the streets.
1 Answer
One relevant term I have frequently seen applied is the phrase "under surveillance," in situations like this one: "From the moment Yuri reached New York, U.S. intelligence agencies kept him under constant surveillance." One aspect of surveillance, when used in this sense, is that the person being watched either never sees the people watching him or her, or catches only fleeting glimpses of them.
Merriam-Webster's Eleventh Collegiate Dictionary (2003) brings out this surreptitious apect of surveillance in its definition of surveillance:
surveillance n (1802) close watch kept over over someone or something (as by a detective)