In American parlance, the brig encompasses three classes of ship: the full-rigged brig (often simply called a "brig"), the hermaphrodite brig, and the brigantine. All American brigs are defined by having exactly two masts that are entirely or partially square-rigged. The foremast of each is always entirely square-rigged; variations in the taller mainmast are what define the different subtypes (The definition of a brig, brigantine, etc. has been subject to variations in nation and history, however, with much crossover between the classes).