Mēg'a-lo-saur' or Mēg'a-lo-sau'rus, n.

n. [Fr. mégalosaure, from Gr. μέγας, μεγάλη, great, and σαῦρος, σαῦρα, lizard.] (Palæon.) A gigantic saurian or lizard, now extinct, whose fossil remains have been found in England and elsewhere.