- : to get rid of as superfluous or encumbering : omit or forgo as part of a plan or as the result of some other decisionmust be prepared to jettison many romantic notions — Christopher Catling
- to drop (cargo) to lighten a ship's load in time of distress
- to drop from an aircraft or spacecraft in flight
- throw or drop (something) from an aircraft or ship.
- "six aircraft jettisoned their loads in the sea"
- the action of jettisoning something."the jettison lever"
definition derived from Merriam Webster