backbreaking

from WordNet (r) 3.0 (2006)

backbreaking
    adj 1: characterized by effort to the point of exhaustion;
           especially physical effort; "worked their arduous way up
           the mining valley"; "a grueling campaign"; "hard labor";
           "heavy work"; "heavy going"; "spent many laborious hours
           on the project"; "set a punishing pace" [syn: {arduous},
           {backbreaking}, {grueling}, {gruelling}, {hard}, {heavy},
           {laborious}, {operose}, {punishing}, {toilsome}]

from Moby Thesaurus II by Grady Ward, 1.0

33 Moby Thesaurus words for "backbreaking":
      Herculean, annoying, arduous, besetting, bothersome, burdensome,
      crushing, effortful, forced, grueling, hard-earned, hard-fought,
      heavy, hefty, irksome, killing, labored, laborious, onerous,
      operose, oppressive, painful, plaguey, punishing, strained,
      strenuous, toilsome, tough, troublesome, trying, uphill, vexatious,
      wearisome

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