(adj.adv.) : nĕfārĭus, a, um, adj.nefas
* Impious, execrable, abominable, nefarious (class.; syn.: impius, sacrilegus): homo nefarius et impius,Cic. Off. 2, 14, 51: nefarius Atreus,Hor. A. P. 186: voluntates consceleratae ac nefariae,Cic. Sull. 9, 28: scelestum ac nefarium facinus,id. Rosc. Am. 13, 37: singularis et nefaria crudelitas,Caes. B. G. 7, 77; Cic. Rep. 3, 9, 14: multa commemorare nefaria in socios,id. Off. 2, 8, 28: nefario scelere se obstringere,Caes. B. C. 2, 32: nuptiae. Gai. Inst. 1, 64.
* Subst.: nĕfārĭum, ii, n., a heinous act, a crime: rem publicam nefario obstringere. Liv 9, 34.—Hence, adv.: nĕfārĭē, impiously, execrably, heinously, abominably: aliquid nefarie flagitioseque facere,Cic. Verr. 1, 13, 37; id. Div. in Caecil. 12, 38: nefarie moliri pestem patriae,id. Cat. 2, 1, 1: nefarie occisus pater,id. Rosc. Am. 11, 30.

s. TLL