sentinel

If musical theater had a canine sentinel, it might well be a standard French poodle.

Beal noted one of the sentinel signs that a farm has been infected is dead barn cats that have drunk the infected, raw milk.

One of the more ambitious scenes was a sentinel attack that decimates the mutants.

Intriguingly, the system being attacked normally works as a sentinel or guard, whose job it is to detect invading viruses.

The area has been named a sentinel landscape, a federally led effort to promote sustainable land-use practices near military installations.