perniciabilis
From LSJ
Latin > English (Lewis & Short)
pernĭcĭābĭlis: e, adj. pernicies,
I destructive, ruinous, pernicious: id perniciabile reo, Tac. A. 4, 34: nix oculis perniciabilis, Curt. 7, 3, 13: pestilentia quae magis in morbos longos quam in perniciabilis evasit, Liv. 27, 23, 7.