Therizinosaurs (once called segnosaurs) were small to giant-sized, mainly herbivorous, theropod dinosaurs that have been found across the Early to Late Cretaceous deposits in Mongolia, China and North America. Various features of the forelimbs, skull and pelvis unite these finds as both theropods and maniraptorans, close relatives to birds. The representative genus, Therizinosaurus, is derived from the Greek θερίζω (therízo, meaning scythe, reap or cut) and σαῦρος (sauros, meaning lizard). The older representative, Segnosaurus, is derived from the Latin word segnis (meaning slow) and the Greek σαῦρος (sauros, meaning lizard).