Picket (noun)

1. A pointed stake, usually of wood, driven into the ground to serve as a marker or fence.
2. A person or group of people who stand outside a building or location as a form of protest or demonstration.

Origin:

Early 17th century (originally denoting a pointed stake for enclosing land or for defense): from french piquet, diminutive of pique "pointed stake", from piquer "to prick", from pic "point".

Examples:

1. The picket fence was made of white wooden stakes.
2. The workers went on strike and set up picket lines.
3. The picket is holding a sign that says "Fair wages now".
4. The union organized a picket in front of the factory.
5. The picket line was peaceful and orderly.