monotreme
Any of the order Monotremata of mammals that lay eggs and have single orifices for urogenital and digestive functions (cloaca); an echidna, platypus or one of their extinct relatives.
Related words
- monotrematous
- monotremous
Where this comes from
This definition is adapted from “monotreme” on Wiktionary, by its contributors, published under CC BY-SA 4.0. This page is published under the same licence.