dinosaur

Children usually learn this noun with direct reference to “any of various extinct, often gigantic, chiefly terrestrial reptiles of the orders Saurischia and Ornithischia that lived in the Mesozoic Era” (AHD). Dinosaur can also be used for “a relic of the past” or “one hopelessly outmoded or unwieldy” (AHD). This word comes from New Latin Dinosauria, the group name, from Dinosaurus, the former genus name. The elements of the name are Greek deinos, “monstrous,” and Greek sauros, “lizard” (AHD). So, a dinosaur is literally a monstrous lizard, be it an extinct reptile or an antiquated system.