ETYM Latin, prob. for asnus: cf. Greek hizein to sit, Skr. âs.
(Irregular plural: anuses).
Excretory opening at the end of the alimentary canal; SYN. arse, arsehole, asshole.
Opening at posterior end of alimentary canal.
Opening at the end of the alimentary canal that allows undigested food and other waste materials to pass out of the body, in the form of feces. It is found in all types of multicellular animal except the coelenterates (sponges) and the platyhelminths (flatworms), which have a mouth only.
1. A fissure in the earth's crust (or in the surface of some other planet) through which molten lava and gases erupt; SYN. volcano, crater.
2. An opening for the escape of gas or air; SYN. venthole, blowhole.
3. External opening of urinary or genital system of a lower vertebrate.