e·chid·na (ih-KID-nuh) n. [NLat. < Lat., viper < Gk. ekhidna.]

1. The spiny anteater, of the family Tachyglossidae in the monotreme order of egg-laying mammals, native to New Guinea and Australia.*

2. In Greek mythology, Echidna (Greek: Εχιδνα, meaning “she viper”) was half woman and half snake, known primarily for being the mother of monsters, including many of the most famous monsters of Greek myth.