The Collaborative International Dictionary of English v.0.48:

Pteranodon \Pte*ran"o*don\, n. [Gr. ? wing + ? priv. + ?, ?, a
   tooth.] (Paleon.)
   A genus of American Cretaceous pterodactyls destitute of
   teeth. Several species are known, some of which had an
   expanse of wings of twenty feet or more.
   [1913 Webster]