Lewis & Short

oenŏthēra, ae, f., or oenŏthēris, ĭdis, f., = οινοθήρα or οἰνοθηρίς (also ŏnŏ-thēra, onŏthūris), a plant, the juice of which, drunk in wine, produces sleep: onothera, sive onear, hilaritatem afferens in vino, Plin. 26, 11, 69, § 111; acc. onothurim, id. 24, 17. 102, § 167; 26, 14, 87, § 146.