miff (n.)youdaoicibaDictYouDict
1620s, "fit of ill humor," perhaps imitative of an exclamation of disgust (compare German muffen "to sulk").
miff (v.)youdaoicibaDictYouDict
1797, "to take offense at;" 1811, "to put out of humor," from miff (n.). Related: miffed; miffing.