[1] : The Collaborative International Dictionary of English v.0.48

credibly \cred"ibly\, adv.
   in a manner inducing belief; as, i have been credibly
   informed of the event.
   1913 webster

[2] : WordNet (r) 2.0

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

Credibly >> C Words
Credibly, definition of term: Credibly
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