1. σερός · seros — Beekes
σερός [adv] - χθές. Ἠλεῖοι ‘yesterday (Elean)’ (H.). 41Ὲ *d'#*ies ‘yesterday’> *ETYM Perhaps from ὄχιεσ-ός, related to Skt. hyds ‘yesterday’ < PIE *d'g*ies, with Elean rhotacism and -6c after νυκτός, etc. Cf. » χθές. — [Beekes, s.v. σερός, p. 1372]