The Collaborative International Dictionary of English v.0.48:

Futility \Fu"til`i*ty\, n. [L. futilitas: cf. F. futilit['e].]
   1. The quality of being talkative; talkativeness;
      loquaciousness; loquacity. [Obs.]
      [1913 Webster]

   2. The quality of producing no valuable effect, or of coming
      to nothing; uselessness.
      [1913 Webster]

            The futility of this mode of philosophizing.
                                                  --Whewell.
      [1913 Webster]

WordNet (r) 3.0 (2006):

futility
    n 1: uselessness as a consequence of having no practical result

Moby Thesaurus II by Grady Ward, 1.0:

108 Moby Thesaurus words for "futility":
   absurdity, aimlessness, bankruptcy, big deal, blank future,
   bleak outlook, bootlessness, counterproductiveness,
   counterproductivity, dead letter, defeat, emptiness, empty sound,
   failure, fatuity, fecklessness, flimsiness, foolishness, frivolity,
   frivolousness, fruitlessness, hollowness, hopelessness, idleness,
   ill success, impoliticalness, impoliticness, impossibility,
   impotence, inadvisability, inanity, inappropriateness, inaptitude,
   incongruity, inconvenience, inconveniency, ineffectiveness,
   ineffectuality, ineffectualness, inefficaciousness, inefficacy,
   ineptitude, inexpectation, inexpedience, inexpediency, infelicity,
   inopportuneness, insignificance, invalidity, levity, lightness,
   losing game, meaninglessness, mere noise, no go, no hope, noise,
   nonaccomplishment, nonsensicality, nonsuccess, not a prayer,
   nugacity, nullity, otiosity, phatic communion, pointlessness,
   profitlessness, purposelessness, rat race, senselessness,
   shallowness, silliness, slenderness, slightness, small hope,
   successlessness, superficiality, the absurd, triflingness,
   triteness, triviality, trivialness, undesirability, unfitness,
   unfittingness, unfortunateness, unhopefulness, unmeaningness,
   unmeetness, unproductiveness, unprofitability, unprofitableness,
   unseasonableness, unseemliness, unsignificancy, unsuccess,
   unsuccessfulness, unsuitability, untimeliness, unwiseness,
   uselessness, vacuity, valuelessness, vanity, vapidity,
   vicious circle, worthlessness, wrongness