Monotreme
WordNet
noun
(1) The most primitive mammals comprising the only extant members of the subclass Prototheria
WiktionaryText
Noun
- A mammal that lays eggs and has a single urogenital and digestive orifice. Only the echidnas and platypuses are included in this group.
Adjective
- Having a single trema, or aperture
- }
Coordinate terms
- atreme
- bitreme
- tritreme
- tetratreme
- pentatreme
- hexatreme
Related terms
- trema
- anatreme
- catatreme
- nomotreme
- pantotreme
- zonotreme