1 The process by which a cell or battery delivers current to an external circuit. A discharge may be continuous or intermittent.
2 The quantity of electricity that is removed from a cell or battery while current is delivered to an external circuit.
It is usually measured in ampere-hours.
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)
International Association of Marine Aids to Navigation and Lighthouse Authorities - AISM