sentry

A guard, especially a soldier posted at a given spot to prevent the passage of unauthorized persons.

The duty of a sentry; watch.

Same as centry, center.

A place of watch; a watch-tower.

Watch; guard: same as sentinel, 1.

One stationed as a guard: same as sentinel, 2.

Acting as a sentry; watching.

A soldier placed on guard; a sentinel.

Guard; watch, as by a sentinel.

a small house or box to cover a sentinel at his post, and shelter him from the weather.