picket

noun

1
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
2
a wooden strip forming part of a fence
3
a vehicle performing sentinel duty
4
a detachment of troops guarding an army from surprise attack
5
a person employed to keep watch for some anticipated event
6
a protester posted by a labor organization outside a place of work

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