1. A common chamber in certain animals (birds, reptiles, amphibians, and some fish) into which the intestinal, urinary, and reproductive tracts empty.
Usage: biology, zoology
2. A sewer or underground passage for waste water in ancient Rome.
Usage: historical

Examples

• Birds have a cloaca instead of separate openings for waste and reproduction.
• The cloaca is a key feature in the anatomy of reptiles and amphibians.
• In ancient Rome, the Cloaca Maxima was one of the oldest and most important sewers.
• Biologists study the cloaca to understand how different animal species manage waste elimination.
• The cloaca serves multiple functions in avian physiology.