The Collaborative International Dictionary of English v.0.48:

Deinosaur \Dei"no*saur\ (d[imac]"n[-o]*s[add]r), n. [NL.]
   (Paleon.)
   See Dinosaur.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Dinosaur \Di"no*saur\, Dinosaurian \Di`no*sau"ri*an\, n. [Gr. ?
   terrible + ? lizard.] (Paleon.)
   One of the Dinosauria. [Written also deinosaur, and
   deinosaurian.]
   [1913 Webster]