jettison

Jettison is a verb meaning to throw or discard something from a vehicle or vessel, especially to lighten a load or improve safety. The noun form jettison refers to the act of discarding or to the items that are discarded. The term derives from the French jeter, meaning “to throw,” and entered nautical English in the 19th century as ships began to shed cargo, ballast, or fuel in response to emergencies or weight management.

In maritime use, jettison typically involves throwing cargo, ballast, or fuel overboard to stabilize a vessel, prevent capsizing, or reduce drag. While it can be a lifesaving measure, modern international regulations restrict the dumping of pollutants and hazardous materials, with exceptions allowed only when necessary for safety or under controlled procedures.

In aviation and spaceflight, jettison describes the intentional discarding of portions of an aircraft or spacecraft to reduce weight or to separate components. Aircraft may jettison fuel to reach a safe landing weight, and space systems may jettison payload fairings, spent stages, or other hardware during ascent, orbital operations, or reentry phases. These actions are carefully designed to minimize risk to people and the environment and are governed by flight rules and mission procedures.

Colloquially, jettison can also mean to abandon or discard plans, ideas, or objects not needed, often for strategic or practical reasons. It denotes a deliberate removal or rejection intended to improve overall performance or safety.