impossibly

from WordNet (r) 3.0 (2006)

impossibly
    adv 1: to a degree impossible of achievement; "long thought to
           be an impossibly difficult operation"; "impossibly far
           from sources of supply" [ant: {possibly}]

from The Collaborative International Dictionary of English v.0.48

Impossibly \Im*pos"si*bly\, adv.
   Not possibly. --Sir. T. North.
   [1913 Webster]

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