noun

1. a stake or slat, usually pointed, used as an upright in a fence, a hitching post for animals, a marker, etc.
2. a group of soldiers or a single soldier stationed, usually at an outpost, to guard a body of troops from surprise attack
3. a ship or airplane that patrols a defense perimeter
4. a person, as a member of a labor union on strike, stationed outside a factory, store, or public building, often carrying a sign, to demonstrate opposition to certain views or practices, keep strikebreakers from entering, or dissuade people from buying

Etymology: Fr piquet < piquer, to pierce < pic, pike

transitive verb

1. to enclose, shut in, or protect with a picket fence or palisade
2. to hitch (an animal) to a picket
3. 1. to post as a military picket
   2. to guard (a body of troops) with a picket
4. to place pickets, or serve as a picket, at (a factory, etc.)

intransitive verb