Cloaca maxima is a Latin term which refers to the largest sewer in ancient Rome. This sewer system was built to channel wastewater, rainwater, and sewage out of the city. There are many synonyms for this term. These include the Roman sewer, the great sewer, the biggest sewer, and the ancient sewer. Other synonyms for cloaca maxima include the main sewer, the primary sewer, and the massive sewer. Each of these terms describes the same structure that provides an essential service for a city or town. While the name may vary, the purpose and function of the cloaca maxima remain the same.