Lewis & Short

Euhan (cf. Lach. ad Lucr. 5, 743; also, Euan, Prisc. 1, 29; not Evan, as in many edd.), m., = Εὐάν, a surname of Bacchus, Lucr. 5, 742; Ov. M. 4, 15; Mart. Cap. 8, § 804.
Hence, euhans, antis (cf. Gr. εὐάζων), adj., crying Euhan! an epithet of the Bacchantes, Cat. 64, 391; Sil. 1, 101; Prop. 2, 3, 18.
Poet. with acc.: euhantes orgia, celebrating the rites of Bacchus with the cry Euhan! Verg. A. 6, 517.