chol·er / ˈkälər/ • n. (in medieval science and medicine) one of the four bodily humors, identified with bile, believed to be associated with a peevish or irascible temperament. Also called yellow bile. ∎ poetic/lit. or archaic anger or irascibility.

choler in medieval science and medicine, one of the four bodily humours, identified with bile, believed to be associated with a peevish or irascible, or choleric, temperament. Also known as yellow bile.

Recorded from late Middle English (also denoting diarrhoea), the word comes from Old French colere ‘bile, anger’, from Latin cholera ‘diarrhoea’ (from Greek kholera), which in late Latin acquired the senses ‘bile or anger’, from Greek kholē ‘bile’.

choler bile XIV; anger XVI. ME. coler(e) — (O)F. colère — L. cholera; see next. In late L. cholera took over the meanings of Gr. kholḗ bile, anger, and became the techn. name for one of the four ‘humours’ of the old physiologists (cf. MELANCHOLY).
So choleric †bilious XIV; irascible, angry XVI. — (O)F. colérique — L. cholericus — Gr. kholerikós.