[1] : The Collaborative International Dictionary of English v.0.48

inadvertent \in`advert"ent\, a. cf. f. inadvertant. see 2d
   in-, and advert.
   not turning the mind to a matter; heedless; careless;
   negligent; inattentive.
   1913 webster

         an inadvertent step may crush the snail
         that crawls at evening in the public path. --cowper.
   -- in`advert"ently, adv.
   1913 webster
see also:
in- advert in`advert"ently 

[2] : WordNet (r) 2.0

inadvertent
     adj : without intention especially resulting from heedless
           action; "with an inadvertent gesture she swept the
           vase off the table"; "accidental poisoning"; "an
           accidental shooting" syn: accidental
see also:
accidental 

[3] : Moby Thesaurus II by Grady Ward, 1.0

89 moby thesaurus words for "inadvertent":
   arbitrary, automatic, capricious, careless, casual,
   culpably negligent, derelict, disregardant, disregardful,
   distracted, distrait, feckless, gut, heedless, ill-advised,
   ill-considered, ill-devised, inattentive, inconsiderate, incurious,
   indeliberate, indifferent, inobservant, involuntary, laissez-faire,
   lax, loose, neglectful, neglecting, negligent, noninterfering,
   nonrestrictive, off-guard, overly permissive, permissive,
   procrastinating, reasonless, reflex, reflexive, regardless,
   relaxed, remiss, scamping, skimping, slack, slighting, slurring,
   snap, spontaneous, thoughtless, unadvised, uncalculated,
   uncalculating, uncaring, uncircumspect, unconscious, unconsidered,
   undeliberate, undeliberated, undesigned, undevised, unguarded,
   unheedful, unheeding, unintended, unintentional, unmarking,
   unmeditated, unmindful, unnoticing, unnoting, unobservant,
   unobserving, unplanned, unpremeditated, unpurposed, unreasoning,
   unreflecting, unreflective, unremarking, unrigorous, unstudied,
   unthinking, unthought, unthoughtful, unwary, unwatchful, unwilled,
   wrecking

Inadvertent >> I Words
Inadvertent, definition of term: Inadvertent
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