Same entry in Photius (rho45 Theodoridis), similar one already in Hesychius rho127. The headword, which must be quoted from somewhere but is not independently attested, is masculine accusative singular or neuter nominative/accusative singular of this adjective.
LSJ suggests that the word is related to the adjective r(wro/s and the verb r(w/nnumi; cf. rho 252.