\Sen"try\, n.; pl. {Sentires}. [Probably from OF.
senteret a little patch; cf. F. sentier path, and OF. sente.
See {Sentinel}.]
1. (Mil.) A soldier placed on guard; a sentinel.
2. Guard; watch, as by a sentinel.
         Here toils, and death, and death's half-brother,
         sleep, Forms terrible to view, their sentry keep.
                                               --Dryden.
{Sentry box}, a small house or box to cover a sentinel at his
   post, and shelter him from the weather.