therapsid

 
Pronunciation: /θɛˈrapsɪd/

noun

  • a fossil reptile of a Permian and Triassic order, the members of which are related to the ancestors of mammals.
    • Order Therapsida, subclass Synapsida: many families and numerous genera, including the cynodonts

Origin:

early 20th century: from modern Latin Therapsida, from Greek thēr 'beast' + hapsis, hapsid- 'arch' (referring to the structure of the skull)