Source : Webster's Revised Unabridged Dictionary (1913)

Plausibly \Plau"si*bly\, adv.
   1. In a plausible manner.

   2. Contentedly, readily. [Obs.]

            The Romans plausibly did give consent. --Shak.

Source : WordNet®

plausibly
     adv : easy to believe on the basis of available evidence; "he
           talked plausibly before the committee"; "he will
           probably win the election" [syn: {credibly}, {believably},
            {probably}] [ant: {incredibly}]