Definition of protorosaur in English:

protorosaur

(also proterosaur)

noun

  • An early fossil reptile of the genus Protorosaurus or the order Protorosauria (now often called Araeoscelidia).

Origin

Mid 19th century; earliest use found in James Dana (1813–1895), geologist, zoologist, and teacher. From scientific Latin Protorosaurus (or Proterosaurus) Protorosaurus: see -saur.

Pronunciation

protorosaur

/ˈprəʊt(ə)rə(ʊ)sɔː/