12th earthly branch: 9-11 p.m., 10th solar month (7th November-6th Dec
Depicts roots of a plant. Based on the original meaning "roots", now written as 荄. The current meaning is a phonetic loan.
《說文》：“亥，荄也。十月微陽起，接盛陰。从，，古文上字，一人男，一人女也。从乙，象褢子咳咳之形。《春秋傳》曰：‘亥有二首六身’。 ，古文。亥為豕，與豕同。亥而生子，復從一起。”
roots