• (a.) Guilty of perfidy; violating good faith or vows; false to trust or confidence reposed; teacherous; faithless; as, a perfidious friend. • (a.) Involving, or characterized by, perfidy. Found on http://thinkexist.com/dictionary/meaning/perfidious/
Per·fid'i·ous (pẽr*fĭd'ĭ*ŭs; 277) adjective [ Latin perfidious .] 1. Guilty of perfidy; violating good faith or vows; false to trust or confidence reposed; teacherous; faithless; as, a perfidious friend. Shak. 2. Involving, or characte... Found on http://www.encyclo.co.uk/webster/P/53