- anus (n.)
[anus 词源字典]
- "inferior opening of the alimentary canal," 1650s, from Old French anus, from Latin anus "ring, anus," from PIE root *ano- "ring." So called for its shape; compare Greek daktylios "anus," literally "ring (for the finger)," from daktylos "finger."[anus etymology, anus origin, 英语词源]