Lewis & Short

crūdesco, dŭi, 3, v. inch. n. [crudus], to grow harsh or violent, to increase, grow worse (poet. and in post-Aug. prose; perh. not before Virg.): coepit crudescere morbus, Verg. G. 3, 504; so, pugnae, id. A. 7, 788: ferrum magicā linguā, Sil. 1, 431: irae, Stat. Th. 2, 680; cf.: crudescente irā, Just. 8, 4, 4: seditio, Tac. H. 3, 10: noxa, Symm. Ep. 8, 57.