3. [Probably so called from the picketing of the horses.] (Mil.) A
detached body of troops serving to guard an army from surprise, and to
oppose reconnoitering parties of the enemy; -- called also outlying
picket.
4. By extension, men appointed by a trades union, or other labor
organization, to intercept outsiders, and prevent them from working for
employers with whom the organization is at variance. [Cant]
5. A military punishment, formerly resorted to, in which the offender
was forced to stand with one foot on a pointed stake.