s ɔr ə s / or / t aɪ ˌ r æ n ə ˈ s ɔr ə s / ; meaning "tyrant lizard", from Greek tyrannos (τύραννος) meaning "tyrant," and sauros (σαῦρος) meaning "lizard") is a genus of coelurosaurian theropod dinosaur . The species Tyrannosaurus rex ( rex meaning "king"