The term engine room refers to the space on a ship, aircraft, or locomotive where the machinery is housed. Synonyms for the phrase include motor room, machinery compartment, power plant, and boiler room. The motor or machinery room is where all the complex equipment that runs a ship or aircraft resides. It requires specialized training to maintain the engine room and keep it running smoothly. The power plant, on the other hand, refers to the major machinery and systems that produce and distribute power across the ship or aircraft. Finally, the boiler room is another synonym used mostly for steamboats, where the boilers were located to generate steam power.