This middle-voice verb describes the nautical action of unloading or discharging a ship's cargo. Classical sources use it for jettisoning cargo in emergency situations or for the routine unloading of freight at port. The middle form emphasizes the sailors' action on their own behalf—getting rid of cargo that belongs to them or that burdens their vessel. Luke employs it to describe Paul's ship arriving at Tyre, where the vessel was scheduled to unload its freight before continuing the journey.