Picket \Pick"et\, v. t. [imp. & p. p. Picketed; p. pr. & vb. n. Picketing.]

1. To fortify with pointed stakes.

2. To inclose or fence with pickets or pales.

3. To tether to, or as to, a picket; as, to picket a horse.

4. To guard, as a camp or road, by an outlying picket.

5. To torture by compelling to stand with one foot on a pointed stake. [Obs.]

Source: Webster's Revised Unabridged Dictionary (1913)
 

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.

2. A pointed pale, used in marking fences.

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]

Source: Webster's Revised Unabridged Dictionary (1913)
 

Piquet \Pi*quet"\, n. [F., prob. fr. pique. See Pique, Pike, and Picket.]

A game at cards played between two persons, with thirty-two cards, all the deuces, threes, fours, fives, and sixes, being set aside. [Written also picket and picquet.]

Source: Webster's Revised Unabridged Dictionary (1913)