Feud
Middle English fede ‘hostility, ill will’, from Old French feide, from Middle Dutch, Middle Low German vēde, of Germanic origin; related to foe.
wiktionary
From northern Middle English fede, feide, from Old French faide, feide, fede, from Old High German fehida, from Proto-West Germanic *faihiþu(“hatred, enmity”) (corresponding to foe + -th), from Proto-Indo-European *peyḱ-(“hostile”). Old English fǣhþ, fǣhþu, fǣhþo(“hostility, enmity, violence, revenge, vendetta”) was directly inherited from Proto-Germanic *faihiþō, and is cognate to Modern German Fehde, Dutch vete(“feud”), Danish fejde(“feud, enmity, hostility, war”), and Swedish fejd(“feud, controversy, quarrel, strife”).
From Medieval Latin feudum. Doublet of fee.
etymonline
feud (n.)
c. 1300, fede "enmity, hatred, hostility," northern English and Scottish, ultimately (via an unrecorded Old English word or Old French fede, faide "war, raid, hostility, hatred, enmity, feud, (legal) vengeance," which is from Germanic) from Proto-Germanic *faihitho (compare Old High German fehida "contention, quarrel, feud"), noun of state from adjective *faiho- (source also of Old English fæhð "enmity," fah "hostile;" German Fehde "feud;" Old Frisian feithe "enmity"). Perhaps from the same PIE source as foe. Sense of "vendetta" is early 15c. Alteration of spelling in 16c. is unexplained. Meaning "state of hostility between families or clans" is from 1580s.
feud (v.)
1670s, from feud (n.). Related: Feuded; feuding.
