Definitions for yellow bile
Random House Webster's College Dictionary
one of the four elemental bodily humors of medieval physiology, regarded as causing anger; choler.
Origin of yellow bile:
yellow bile, choler(noun)
a humor that was once believed to be secreted by the liver and to cause irritability and anger
One of the four humours of ancient and mediaeval physiology, that was believed to be secreted by the liver and to cause irascibility, anger, and bad temper when present in excess.