Definition of plesiosaurian in English:

plesiosaurian

adjective

  • Of, relating to, or characteristic of a plesiosaur; belonging to the infraorder Plesiosauria.

noun

  • A reptile of the order Plesiosauria ; a plesiosaur.

Origin

Mid 19th century; earliest use found in Richard Owen (1804–1892), comparative anatomist and palaeontologist. From either plesiosaur or Plesiosaurus + -ian.

Pronunciation

plesiosaurian

/ˌpliːzɪəˈsɔːrɪən/