'Mastodonsaurus' definitions:

Definition of 'Mastodonsaurus'

From: GCIDE

Mastodonsaurus \Mas`to*don*sau"rus\, n. [NL., fr. E. Mastodon + Gr. say^ros a lizard.] (Paleon.) A large extinct genus of labyrinthodonts, found in the European Triassic rocks. [1913 Webster]