stegosaurus (n.) Look up stegosaurus at Dictionary.com
type of plant-eating dinosaur, 1892, from Modern Latin order name Stegosauria (O.C. Marsh, 1877), from comb. form of Greek stegos "a roof" (related to stege "covering," stegein "to cover," from PIE root *(s)teg- (2) "to cover," especially "cover with a roof" (source also of Sanskrit sthag- "cover, conceal, hide;" Latin tegere "to cover;" Lithuanian stegti "roof;" Old Norse þekja, Old English þeccan "thatch;" Dutch dekken, German decken "to cover, put under roof;" Irish tuigiur "cover," tech "house;" Welsh toi "thatch, roof," ty "house") + -saurus. The back-armor plates in the fossilized remains look like roof tiles.