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

unaccountable \un`account"able\, a.
   1. not accountable or responsible; free from control.
      --south.
      1913 webster

   2. not to be accounted for; inexplicable; not consonant with
      reason or rule; strange; mysterious.
      1913 webster -- un`account"ableness, n. --
      un`account"ably, adv.
      1913 webster
      1913 webster
see also:
un`account"ableness un`account"ably 

[2] : WordNet (r) 2.0

unaccountable
     adj 1: not to be accounted for or explained; "perceptible only as
            unaccountable influences that hinder progress"; "an
            unexplainable fear" syn: unexplainable
     2: free from control or responsibility
see also:
unexplainable 

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

179 moby thesaurus words for "unaccountable":
   adrift, afloat, agnostic, aimless, alternating, ambiguous,
   amorphous, antic, baffling, bizarre, capricious, casual, causeless,
   chancy, changeable, changeful, chartered, designless, desultory,
   deviable, dicey, disobedient, dizzy, doubting, driftless,
   dysteleological, eccentric, enwrapped in mystery, equivocal,
   erratic, excepted, excused, exempt, exempted, extraordinary,
   fanciful, fantastic, fast and loose, favored, fickle, fitful,
   flickering, flighty, flitting, fluctuating, freakish, giddy,
   haphazard, headstrong, heady, hesitant, hesitating, immune,
   impetuous, impossible, impulsive, incalculable, incomprehensible,
   inconceivable, inconsistent, inconstant, incredible, indecisive,
   indefinable, indemonstrable, indiscriminate, inexplicable,
   inextricable, infirm, inscrutable, insoluble, insolvable,
   insubordinate, irregular, irresolute, irresponsible, lawless,
   let off, licensed, licentious, mazy, mercurial, mindless, moody,
   mutinous, mysterious, mystic, odd, peculiar, permitted, polysemous,
   privileged, promiscuous, purposeless, puzzling, rambling, rampant,
   random, reinless, released, restless, roving, scatterbrained,
   self-willed, shapeless, shifting, shifty, shuffling, skeptical,
   spared, spasmodic, spineless, stochastic, strange, stray,
   touch-and-go, unanswerable, unbelievable, unbridled, uncanny,
   uncertain, unchecked, unconfirmable, uncontrolled, unconvinced,
   uncurbed, undefinable, undependable, undirected, undisciplined,
   undivinable, unexpected, unexplainable, unexplained, unfathomable,
   unfixed, unforeseeable, ungoverned, unheard-of, unimaginable,
   unintelligible, uninterpretable, unliable, unmotivated, unorthodox,
   unpersuaded, unpredictable, unprovable, unreined, unreliable,
   unrestrained, unsettled, unsolvable, unstable, unstable as water,
   unstaid, unsteadfast, unsteady, unsubject, unsure, unusual,
   unverifiable, vacillating, vagrant, variable, vicissitudinary,
   vicissitudinous, volatile, wandering, wanton, wavering, wavery,
   wavy, wayward, weird, whimsical, wildcat, willful, wishy-washy

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