Picket guard

Picket \Pick"et\, n. [F. piquet, properly dim. of pique spear,
   pike. See {Pike}, and cf. {Piquet}.]
   1. A stake sharpened or pointed, especially one used in
      fortification and encampments, to mark bounds and angles;
      or one used for tethering horses.
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   2. A pointed pale, used in marking fences.
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   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}.
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   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]
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   5. A military punishment, formerly resorted to, in which the
      offender was forced to stand with one foot on a pointed
      stake.
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   6. A game at cards. See {Piquet}.
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   {Inlying picket} (Mil.), a detachment of troops held in camp
      or quarters, detailed to march if called upon.

   {Picket fence}, a fence made of pickets. See def. 2, above.
      

   {Picket guard} (Mil.), a guard of horse and foot, always in
      readiness in case of alarm.

   {Picket line}. (Mil.)
      (a) A position held and guarded by small bodies of men
          placed at intervals.
      (b) A rope to which horses are secured when groomed.

   {Picketpin}, an iron pin for picketing horses.
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