Bile comes from the Latin word for bile, bilis.

The Greek word for bile is cholé and is an oft used combining form: a cholecystectomy is the removal of the gall bladder, literally, "removal of the bile bag" (cyst is derived from the Greek kystis, bag or pouch). Cholecystokinin (CCK) is a hormone that stimulates gall bladder contractions, among other functions (-kinin comes from the Greek kinein, to move or stimulate).

To the ancient Greeks and Romans and other believers in the "four humors", melancholy, from melos (Greek for black) and cholé, was thought caused by an excess of "black bile". The word choleric, meaning easily angered or annoyed, stems from the notion that excessive "yellow bile" was responsible for one's ill-temper. Bile, in its non-physiological sense, still refers to a choleric disposition (as in "full of bile") and bilious, from bilis, refers to someone who is peevish or, logically enough, ill-humored.

Gall comes from the Anglo-Saxon word for bile, galla; thus the "gall bladder", the organ that stores and concentrates bile.