The definition of dun is a dull grayish-brown.(adjective)
An example of something dun is moldy chocolate.
Dun is defined as a dull grayish-brown color or something that is that color.(noun)
An example of dun is brown hair that is starting to grey.
See dun in Webster's New World College Dictionary
Origin: ME & OE, akin to OS, chestnut-brown, ult. (? via Celt) < IE *dhus-no < base *dhus, dust-colored: see fury
See dun in American Heritage Dictionary 4
transitive verb dunned dunned, dun·ning, duns
Origin: Origin unknown.
Origin: Middle English
Origin: , from Old English dunn
Origin: , perhaps of Celtic origin.
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