6th earthly branch: 9-11 a.m., 4th solar month (5th May-5th June), yea
Depicts a snake-like creature. Based on the original meaning "a type of snake creature". The current meaning is a phonetic loan.
《說文》：“巳，巳也，四月陽气巳出，陰气巳藏，萬物見，成文章，故巳為蛇。象形。”
a type of snake creature