late 13c., "to rub down a horse," from Anglo-French curreier "to curry-comb a horse," from Old French correier "put in order, prepare, curry," from con-, intensive prefix (see com-), + reier "arrange," from a Germanic source (see ready). Related: Curried; currying.

To curry favor "flatter, seek favor by officious show of courtesy or kindness" is an early 16c. folk-etymology alteration of curry favel (c. 1400) from Old French correier fauvel "to be false, hypocritical," literally "to curry the chestnut horse," chestnut horses in medieval French allegories being symbols of cunning and deceit. Compare German den falben (hengst) streichen "to flatter, cajole," literally "to stroke the dun-colored horse."

Old French fauvel (later fauveau) "fallow, dun," though the exact color intended in the early uses is vague, is a diminutive of fauve "fawn-colored horse, dark-colored thing, dull," for which see Fauvist. The secondary sense here is entangled with similar-sounding Old French favele "lying, deception," from Latin fabella, diminutive of fabula (see fable (n.)). In Middle English, favel was a common name for a horse, while the identical favel or fauvel (from Old French favele) meant "flattery, insincerity; duplicity, guile, intrigue," and was the name of a character in "Piers Plowman."