'Perfidiously' definitions:
Definition of 'perfidiously'
From: WordNet
adverb
In a perfidious manner; "he was playing perfidiously one side against the other"
Definition of 'Perfidiously'
From: GCIDE
- Perfidiously \Per*fid"i*ous*ly\, adv. In a perfidious manner. [1913 Webster]