A stake driven into the ground. / (historical) A type of punishment by which an offender had to rest his or her entire body weight on the top of a small stake.

(intransitive) To protest, organized by a labour union, typically in front of the location of employment. / (transitive) To enclose or fortify with pickets or pointed stakes.

simple past tense and past participle of picket

A simple fence made from wooden pickets, connected by horizontal bars. / A series of spaced perpendicular striations that occasionally occur in aurorae.

(rare) A line or rope held by one or many pickets, chiefly one used for tethering horses. / (military, rare) A barrier or fortification formed by pickets; a stockade.

plural of picket fence

(Australia) A type of pointed metal fence post, consisting of three stips of metal at equal angles to each other.

plural of star picket

A wooden building made by fitting boards across a framework of upright poles, often constructed as part of an outpost or as the first shelter in a new homestead.

(UK) A person or group of people who can be rapidly deployed to different locations in order to picket workplaces (take part in blockades or other protests) during an industrial dispute (dispute between workers and employers).