肛門[koumon] anus
脱肛[dakkou] anal prolapse
肛門学[koumongaku] proctology
肛門科[koumonka] proctology clinic
肛門出血[koumonshukketsu] anal bleeding

肛門上皮[koumonjouhi] anal epithelium
肛門期[koumonki] anal stage
内肛動物[naikoudoubutsu] entoproct (any animal of phylum Entoprocta)
外肛動物[gaikoudoubutsu] Bryozoa animal
肛門性交[koumonseikou] anal intercourse