intransitive. To act as sentinel, stand sentinel, keep guard. literal and figurative. Obsolete. rare.

Military and Navy. An armed soldier or marine posted at a specified point to keep guard and to prevent the passing of an unauthorized person; spec…

Military. intransitive. To post oneself as a picket, to act on picket duty. Obsolete.

intransitive. To perform the office of a sentry.

transitive. To follow or go over (a prescribed route) in the course of official duty (cf. to go (also walk, march, etc.) one's round (also rounds) at…