/duy"neuh sawr'/ , n.
1. any chiefly terrestrial, herbivorous or carnivorous reptile of the extinct orders Saurischia and Ornithischia, from the Mesozoic Era, certain species of which are the largest known land animals.
2. something that is unwieldy in size, anachronistically outmoded, or unable to adapt to change: The old steel mill was a dinosaur that cost the company millions to operate.
[ Dinosaurus (1841), orig. a genus name. See DINO-, -SAUR ]