The Collaborative International Dictionary of English v.0.48:

throw away \throw away\ v. t.
   1. to discard.
      [PJC]

   2. to waste or squander.
      [PJC]
      [1913 Webster]

WordNet (r) 3.0 (2006):

throw away
    v 1: throw or cast away; "Put away your worries" [syn:
         discard, fling, toss, toss out, toss away, chuck
         out, cast aside, dispose, throw out, cast out,
         throw away, cast away, put away]
    2: get rid of; "he shed his image as a pushy boss"; "shed your
       clothes" [syn: shed, cast, cast off, shake off,
       throw, throw off, throw away, drop]

Moby Thesaurus II by Grady Ward, 1.0:

124 Moby Thesaurus words for "throw away":
   abandon, abjure, blow, blunder away, boot out, bounce, brush aside,
   cashier, cast, cast aside, cast away, cast off, cast out, chuck,
   chuck out, consume, contemn, contradict, declaim, decline,
   deep-six, defenestrate, deny, despise, detrude, disapprove,
   discard, discharge, disclaim, discount, disdain, dismiss, disown,
   dispel, dispose of, disregard, dissipate, ditch, do away with,
   dump, eighty-six, eject, eliminate, except, exclude, expel,
   exterminate, extrude, fling off, fool away, forswear, fritter,
   gamble away, get quit of, get rid of, get shut of, give away,
   give the hook, go through, grimace, ham, ham it up,
   hang the expense, heave out, ignore, jettison, jilt, junk,
   kick downstairs, kick out, lavish, liquidate, mug, obtrude, oust,
   out-herod Herod, overact, overdramatize, part with, pass by,
   pass up, purge, push aside, put out, rant, rebuff, recant, refuse,
   refuse to consider, reject, remove, renounce, repel, repudiate,
   repulse, roar, run through, scatter, scout, scrap, seize the day,
   shake off, shed, shoo, shove away, slather, slough, sow broadcast,
   spout, spurn, squander, throw money around, throw off, throw out,
   throw over, throw overboard, thrust out, toss out, toss overboard,
   trifle away, turn away, turn out, underact, waive