Picket
late 17th century (denoting a pointed stake, on which a soldier was required to stand on one foot as a military punishment): from French piquet ‘pointed stake’, from piquer ‘to prick’, from pic ‘pike’.
wiktionary
From French piquet, from piquer(“to pierce”).
etymonline
picket (n.)
1680s, "pointed post or stake (usually of wood, for defense against cavalry, etc.)," from French piquet "pointed stake," from piquer "to pierce" (see pike (n.1)). Also "one of a number of pointed bars used to make a fence," hence picket-fence (1817). The sense of "troops posted in front of an army to give notice of the approach of the enemy" is recorded from 1761; that of "striking workers stationed to prevent others from entering a factory" is from 1867. Picket-line is by 1856 in the military sense, by 1945 of labor strikes.
picket (v.)
1745, "to enclose or fortify with pointed stakes," from picket (n.). Meaning "to place or post as a guard of observation" is by 1775. The sense in labor strikes, protests, etc., is attested from 1867. Related: Picketed; picketing.
