Lewis & Short

Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.

pernĭcĭōsē, adv., v. perniciosus fin.

pernĭcĭōsus, a, um, adj. [pernicies], destructive, ruinous, baleful, pernicious (syn.: exitialis, capitalis): perniciosae leges, Caes. B. C. 1, 7: scripta auctori perniciosa suo, Ov. Tr. 5, 1, 68.
Comp.: morbi animi perniciosiores sunt, quam corporis, Cic. Tusc. 3, 3, 5; Sall. J. 46, 8.
Sup.: perniciosissimum fore, Nep. Ages. 6, 2; Inscr. Grut. 113, 2.
As subst.: pernĭcĭōsa, ōrum, n., baneful things: petuntur, Juv. 10, 54; cf.: inter perniciosissima numerare, Vell. 2, 7, 5.
Hence, adv.: pernĭcĭōsē, destructively, ruinously, perniciously: multa perniciose, multa pestifere sciscuntur in populis, Cic. Leg. 2, 5, 13: luxuriat vitis, Plin. 17, 22, 35, § 178.
Comp., Cic. Leg. 3, 14, 32.
Sup., Aug. Ep. 39.