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

unthinking \unthink"ing\, a.
   1. not thinking; not heedful; thoughtless; inconsiderate; as,
      unthinking youth.
      1913 webster

   2. not indicating thought or reflection; thoughtless.
      1913 webster

            with earnest eyes, and round unthinking face,
            he first the snuffbox opened, then the case. --pope.
      1913 webster -- unthink"ingly, adv. --
      unthink"ingness, n.
      1913 webster
see also:
unthink"ingly unthink"ingness 

[2] : WordNet (r) 2.0

unthinking
     adj 1: not exhibiting or characterized by careful thought syn: unreflective,
             unthoughtful
     2: without care or thought for others; "the thoughtless saying
        of a great princess on being informed that the people had
        no bread; `let them eat cake'" syn: thoughtless, uncaring
     3: mentally sluggish syn: lumpish, lumpen
     adv : in a thoughtless manner; "he stared thoughtlessly at the
           picture" syn: thoughtlessly, unthinkingly ant: thoughtfully
see also:
unreflective unthoughtful thoughtless uncaring lumpish lumpen 
thoughtlessly unthinkingly thoughtfully 

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

163 moby thesaurus words for "unthinking":
   airy, arbitrary, automatic, blank, blankminded, blind, brainless,
   calm, capricious, careless, casual, compulsive, conditioned, crazy,
   cursory, degage, discourteous, disregardant, disregardful,
   easygoing, empty, empty-headed, fatuous, feckless, flippant,
   foolish, forced, forgetful, free and easy, hasty, headless,
   heedless, idiotic, ignorant, ill-advised, ill-considered,
   ill-contrived, ill-devised, ill-gauged, ill-judged, illogical,
   imbecilic, impolite, impolitic, imprudent, impulsive, inadvertent,
   inadvisable, inane, incogitant, inconsiderate, indifferent,
   indiscreet, inept, inexpedient, injudicious, insane, insensate,
   insouciant, instinctive, involuntary, irrational, lackbrained,
   lazy, lean-minded, lean-witted, mad, mechanical, mindless,
   misadvised, misguided, moronic, myopic, neglectful, nirvanic,
   nonsensical, not bright, oblivious, of little brain, offhand,
   passive, pea-brained, perfunctory, pin-brained, quietistic, rash,
   reasonless, reckless, reflex, reflexive, regardless, relaxed,
   respectless, rude, senseless, short-sighted, shortsighted, silly,
   slackminded, slackwitted, stupid, tactless, thoughtfree,
   thoughtless, tranquil, unaccommodating, unadvised, uncalculating,
   uncaring, uncivil, uncomplaisant, unconscious, unconsidered,
   uncooperative, undesigned, undiplomatic, undiscerning,
   undiscriminating, unforeseeing, ungifted, unguarded, unguided,
   unheedful, unheeding, unhelpful, unideaed, unintellectual,
   unintelligent, unintended, unintentional, unmeant, unmeditated,
   unmindful, unobliging, unoccupied, unperceiving, unperceptive,
   unplanned, unpremeditated, unprepared, unprompted, unpurposed,
   unready, unreasonable, unreasoning, unreflecting, unreflective,
   unseeing, unsensible, unsolicitous, unsound, untactful, untalented,
   unthought-of, unthoughtful, unwilled, unwilling, unwise, unwitting,
   vacant, vacuous, witless, wrecking

Unthinking >> U Words
Unthinking, definition of term: Unthinking
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