The Collaborative International Dictionary of English v.0.48:

Procrastination \Pro*cras`ti*na"tion\, n. [L. procrastinatio:
   cf. F. procrastination.]
   The act or habit of procrastinating, or putting off to a
   future time; delay; dilatoriness.
   [1913 Webster]

         Procrastination is the thief of time.    --Young.
   [1913 Webster]

WordNet (r) 3.0 (2006):

procrastination
    n 1: the act of procrastinating; putting off or delaying or
         defering an action to a later time [syn: procrastination,
         cunctation, shillyshally]
    2: slowness as a consequence of not getting around to it [syn:
       dilatoriness, procrastination]

Moby Thesaurus II by Grady Ward, 1.0:

100 Moby Thesaurus words for "procrastination":
   Fabian policy, Micawberism, a wise passiveness, backwardness,
   contemplation, contemplative life, continuation, culpa,
   culpable negligence, dalliance, dallying, dawdling, default,
   dereliction, dilatoriness, dillydallying, disregard,
   do-nothing policy, do-nothingism, do-nothingness, dormancy,
   extension, failure, hesitation, hold-off, idleness, immobility,
   inaction, inactivity, inadvertence, inadvertency, inattention,
   indolence, inertia, inertness, laches, lag, lagging, laissez-aller,
   laissez-faire, laissez-faireism, lapse, laxity, laxness,
   lengthening, lingering, loitering, lollygagging, looseness,
   meditation, mugwump, neglect, neglectfulness, negligence,
   neutralism, neutrality, neutralness, nonfeasance, noninterference,
   noninvolvement, nonparticipation, nonperformance, nonresistance,
   nonrestriction, nonviolence, nonviolent resistance, omission,
   overlooking, oversight, pacifism, paralysis, passive resistance,
   passive self-annihilation, passiveness, passivism, passivity,
   permissiveness, policy, poor stewardship, prolongation,
   protraction, quiescence, quietism, remissness, shilly-shallying,
   slackness, slight, slowness, stagnancy, stagnation, stall,
   standpattism, stasis, tarrying, temporization, unrigorousness,
   vegetation, vita contemplativa, waiting game,
   watching and waiting