Siege train is a term used to describe the artillery and other equipment required to besiege a fortification. However, there are several other words that can be used as synonyms for siege train, including siege engine, battering ram, and trebuchet. A siege engine refers to any weapon or device used during a siege to breach or defend fortifications, such as catapults, ballistae, or other projectile weapons. A battering ram is a large wooden or metal device used to break down doors or walls. A trebuchet is a type of siege engine that uses a counterweight to hurl heavy projectiles at a target. All of these words can be used interchangeably with siege train, depending on the context and the specific equipment being used in the siege.