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

unattainable \unattainable\
   see attainable.
see also:
attainable 

[2] : WordNet (r) 2.0

unattainable
     adj : impossible to achieve; "an unattainable goal" syn: unachievable,
            undoable, unrealizable
see also:
unachievable undoable unrealizable 

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

37 moby thesaurus words for "unattainable":
   beyond one, beyond reach, closed forever to, closed to,
   impenetrable, impervious, impracticable, impractical, inaccessible,
   infeasible, inoperable, insuperable, insurmountable, lost to,
   out of reach, too much for, un-come-at-able, unaccessible,
   unachievable, unapproachable, unavailable, uncompassable,
   undiscoverable, undoable, uneffectible, unfeasible, ungetatable,
   ungettable, unnegotiable, unobtainable, unperformable,
   unprocurable, unreachable, unrealizable, unsecurable,
   unsurmountable, unworkable

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