picket

(noun) a person employed to keep watch for some anticipated event. Synonyms: lookout, lookout man, sentinel, sentry, watch, spotter, scout.

(noun) a detachment of troops guarding an army from surprise attack.

(noun) a protester posted by a labor organization outside a place of work.

(noun) a vehicle performing sentinel duty.

(noun) a wooden strip forming part of a fence. Synonyms: pale.

(noun) a form of military punishment used by the British in the late 17th century in which a soldier was forced to stand on one foot on a pointed stake. Synonyms: piquet.

(verb) serve as pickets or post pickets. Example: "Picket a business to protest the layoffs."

(verb) fasten with a picket. Example: "Picket the goat."