1. perfidia — de Vaan
perfidia 'faithlessness* (PL+), perfididsus 'treacherous' (PL+); confidere 'to put one's trust in, be sure' (PL+), confidentia 'self-confidence' (Naev.+), confidentiloquus 'speaking audaciously' (PL), dijfidere 'to have no confidence in' (PL+). Pit *feipe- [v.], *feipo- [adj.], *fip-e- [£], *foipo- [m.], *feip-os- [nj 'trust'. It. cognates: U. kumpifiatu, kupifiatu, combifiatu [3s.ipv.II]3 kupifiaia [3s.pr.sb.], … — [de Vaan, s.v. perfidia, p. 232]