feud (n.) Look up feud at Dictionary.com
c.1300, fede "enmity, hatred, hostility," northern English and Scottish; perhaps from an unrecorded Old English word or else from Old French fede, which is from Germanic (compare Old High German fehida "contention, quarrel, feud"), from Proto-Germanic *faihitho noun of state from adjective *faiho- (cognates: Old English fæhð "enmity," fah "hostile;" German Fehde "feud;" Old Frisian feithe "enmity"), from PIE root *peig- (2), also *peik- "evil-minded, hostile" (see foe). Sense of "vendetta" is early 15c. Alteration of spelling in 16c. is unexplained.
feud (v.) Look up feud at Dictionary.com
1670s, from feud (n.). Related: Feuded; feuding.