1. 下水か地上水を運び去る排水管(a waste pipe that carries away sewage or surface water)
2. 腸管、生殖管、そして尿路に開口している消化管の端の空洞(鳥類、爬虫類、両生類、ほとんどの魚類、および単孔類、ただし哺乳動物は除く)(the cavity (in birds, reptiles, amphibians, most fish, and monotremes but not mammals) at the end of the digestive tract into which the intestinal, genital, and urinary tracts open)