A war-galley, ancient is a type of boat used in naval warfare in the past. It is characterized by having three or two banks of oars. The TRIREME, which has seven letters, is an example of a war-galley with three banks of oars, while the BIREME, which has six letters, is an example of a war-galley with two banks of oars. These boats were used by many ancient civilizations, such as the Greeks and Romans, for naval battles.