The gallows was a device used for the death penalty in some humanoid civilizations. It consisted of two standing posts supporting a crossbeam from which a noose was suspended. With this device, the executioners hanged the criminal, resulting in the breakage of the neck and the individual dying from asphyxiation.
In 2152, the military of the Kultarey government on Gosis' species homeworld sentenced Jonathan Archer and Malcolm Reed to death by the gallows. Fortunately, the Starfleet officers were able to escape before their sentence was carried out. (ENT: "The Communicator")