[jet.ti.son] n [ME jetteson, fr. AF getteson, fr. OF getaison action of throwing, fr. L jactation-, jactatio, fr. jactare--more at jet] (15c): a voluntary sacrifice of cargo to lighten a ship's load in time of distress
[2]jettison vt (1848) 1: to make jettison of
2: to get rid of as superfluous or encumbering: discard
3: to drop from an airplane or spacecraft in flight -- jet.ti.son.able adj