VERB (2)

1. throw away, of something encumbering;

2. throw as from an airplane;

The Collaborative International Dictionary of English v.0.48:

Jettison \Jet"ti*son\ n. [See Jetsam.]
   [1913 Webster]
   1. (Mar. Law) The throwing overboard of goods from necessity,
      in order to lighten a vessel in danger of wreck.
      [1913 Webster]

   2. See Jetsam, 1.
      [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

118 Moby Thesaurus words for "jettison":
   abandon, abandonment, abdicate, absentation, back out, beg off,
   boot out, booting out, bounce, cashier, cast, cast aside,
   cast away, cast off, cast out, castaway, casting away, castoff,
   cessation, chuck, chuck out, cry off, deep six, deep-six,
   defenestrate, defenestration, depart from, desuetude, detrude,
   detrusion, discard, discarding, discharge, disposal, dispose of,
   disposition, disuse, ditch, drop out, dump, dumping, eighty-six,
   eject, ejection, ejectment, eliminate, elimination, evacuate,
   evacuation, exclude, expel, expulsion, extrude, extrusion, forsake,
   forsaking, get quit of, get rid of, get shut of, give away,
   give the hook, go back on, heave out, jettisoning, jilt, junk,
   junking, kick downstairs, kick out, kicking downstairs, leave,
   leave behind, leave flat, leaving, maroon, obtrude, obtrusion,
   oust, ouster, ousting, part with, pull out, pulling out, put out,
   quit, quit cold, refuse, reject, rejectamenta, rejection,
   relegation, removal, remove, renege, riddance, say goodbye to,
   scrap, scrapping, shed, slough, stand down, take leave of,
   the boot, the bounce, throw away, throw out, throw over,
   throw overboard, throwaway, throwing out, throwing overboard,
   thrust out, toss out, toss overboard, turn out, vacate, withdraw,
   withdrawal