Dinosaurs are named in Latin and Greek and one (Irratator) is english! The word "dinosaur" is derived from the words Deino (meaning "terrible) and Sauros (meaning lizard/reptile). All dinosaurs also had last names, although these are rarely used outside scholastic material. Last names are frequently based off either the discoverer, or the location.
NOTE:If you want to know what different dinosaur names mean ask them what they mean on Wikianswers.