ĕchidna, ae, f., = ἔχιδνα,
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.
A Lernaea, the Lernaean hydra , killed by Hercules , Ov. M. 9, 69; 158; id. F. 5, 405.—
B A monster , half woman and half serpent , the mother of Cerberus , Ov. M. 4, 501.
V —Hence, Echidnēus , a, um, adj., of Echidna : canis, i. e. Cerberus , Ov. M. 7, 408.