undeterminable

from WordNet (r) 3.0 (2006)

undeterminable
    adj 1: not capable of being definitely decided or ascertained
           [syn: {indeterminable}, {undeterminable}] [ant:
           {determinable}]

from The Collaborative International Dictionary of English v.0.48

Undeterminable \Un`de*ter"mi*na*ble\, a.
   Not determinable; indeterminable. --Locke.
   [1913 Webster]

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