cestros

πολλῶν ὁ καιρὸς γίγνεται διδάσκαλος → the critical moment will turn out to be the teacher of many things

Latin > English (Lewis & Short)

cestros: i, f., = κέστρος,
I the plant betony: Betonica officinalis, Linn.; Plin. 25, 8, 46, § 84.