I.an adder, viper. The Furies were said to have them twined in their hair; “hence: stipite te Stygio tumidisque adflavit Echidnis E tribus una soror,” Ov. M. 10, 313.—
II. Nom. prop.
B. A monster, half woman and half serpent, the mother of Cerberus, Ov. M. 4, 501.—Hence, Echidnēus , a, um, adj., of Echidna: “canis,” i. e. Cerberus, Ov. M. 7, 408.