impracticably

from WordNet (r) 3.0 (2006)

impracticably
    adv 1: to an impracticable degree; "this is still impracticably
           high"

from The Collaborative International Dictionary of English v.0.48

Impracticably \Im*prac"ti*ca*bly\, adv.
   In an impracticable manner.
   [1913 Webster]

         Morality not impracticably rigid.        --Johnson.
   [1913 Webster]