indemonstrable

from The Collaborative International Dictionary of English v.0.48

Indemonstrable \In`de*mon"stra*ble\, a. [L. indemonstrabilis.
   See {In-} not, and {Demonstrable}.]
   Incapable of being demonstrated. --
   {In`de*mon"stra*ble*ness}, n.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

32 Moby Thesaurus words for "indemonstrable":
      agnostic, ambiguous, capricious, chancy, changeable, dicey,
      doubting, equivocal, erratic, fickle, hesitant, hesitating,
      incalculable, indecisive, irresolute, polysemous, skeptical,
      touch-and-go, unaccountable, uncertain, unconfirmable, unconvinced,
      undivinable, unforeseeable, unpersuaded, unpredictable, unprovable,
      unsure, unverifiable, variable, wavering, whimsical

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