Synonyms for Picket (same or very similar meaning)
WordNet sense 1 (a person employed to watch for something to happen):
lookout, scout, sentinel, sentry, spotter, watch, lookout man
WordNet sense 2 (a wooden strip forming part of a fence):
pale
WordNet sense 3 (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):
piquet
From the ODE community, based on WordNet
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