Source : Webster's Revised Unabridged Dictionary (1913)

Possibly \Pos"si*bly\, adv.
   In a possible manner; by possible means; especially, by
   extreme, remote, or improbable intervention, change, or
   exercise of power; by a chance; perhaps; as, possibly he may
   recover.

         Can we . . . possibly his love desert?   --Milton.

         When possibly I can, I will return.      --Shak.

Source : WordNet®

possibly
     adv 1: by chance; "perhaps she will call tomorrow"; "we may
            possibly run into them at the concert"; "it may
            peradventure be thought that there never was such a
            time" [syn: {perchance}, {perhaps}, {maybe}, {mayhap},
             {peradventure}]
     2: with a possibility of becoming actual; "introducing possibly
        dangerous innovations"; "he is potentially dangerous";
        "potentially useful" [syn: {potentially}]
     3: in a manner or to a degree possible of conceiving; "is it
        possibly true?" [ant: {impossibly}]
     4: to a degree possible of achievement or by possible means;
        "they can't possibly get here in time for the funeral?"
        [ant: {impossibly}]