Noun
1. horse of a dull brownish gray color
2. a color varying around light grayish brown;
"she wore a dun raincoat"Verb
1. treat cruelly;
"The children tormented the stuttering teacher"2. persistently ask for overdue payment;
"The grocer dunned his customers every day by telephone"3. cure by salting;
"dun codfish"4. make a dun color
Adjective
1. of a dull grayish brown to brownish gray color;
"the dun and dreary prairie"