dun
1. dun \'d*n\ \'d*n-n*s\ aj [ME, fr. OE dunn - more at DUSK] 1a: having a dun color of a horse 1b: exhibiting reduced hair pigmentation 2: marked by dullness and drabness - dun.ness n 2. dun n 1: a dun horse 2: a variable color averaging a nearly neutral slightly brownish dark gray 3a: a subadult mayfly; also : an artificial fly tied to imitate suc h an insect 3b: CADDIS FLY 3. dun vt or dunned; or dun.ning [origin unknown] 1: to make persistent demands upon for payment 2: to plague or pester constantly 4. dun n 1: one who duns 2: an urgent request; esp : a demand for payment
Webster's English Dictionary