Source : Webster's Revised Unabridged Dictionary (1913)

Ambiguously \Am*big"u*ous*ly\, adv.
   In an ambiguous manner; with doubtful meaning.

Source : WordNet®

ambiguously
     adv : in an ambiguous manner; "this letter is worded ambiguously"
           [syn: {equivocally}] [ant: {unambiguously}]