1660s, from French bile (17c.) "bile," also, informally, "anger," from Latin bilis "fluid secreted by the liver," also one of the four humors (also known as choler), thus "anger, peevishness" (especially as black bile, 1797).
bile (bīl)
n.
A bitter, alkaline, brownish-yellow or greenish-yellow fluid that is secreted by the liver, stored in the gallbladder, and discharged into the duodenum and aids in the emulsification, digestion, and absorption of fats. Also called gall1.
Either of two bodily humors, black bile or yellow bile, in ancient and medieval physiology.
A bitter fluid produced by the liver and stored in the gallbladder. Bile is discharged into the small intestine when needed to aid in the digestion of fats (see digestive system).
Note: Bile is sometimes used figuratively to denote bitterness in general: “His writing was full of bile.”