ty·ran·no·saur·us 
(tĭ-răn′ə-sôrəs, tī-)
(tĭ-răn′ə-sôrəs, tī-)n.
1. Any of various tyrannosaurid dinosaurs of the genus Tyrannosaurus, having a large head and teeth and short forelimbs, and including T. rex and possibly some other species. Also called tyrannosaur.
2. See T. rex.
[New Latin Tyrannosaurus, genus name : Greek turannos, tyrant + sauros, lizard.]