—see Doun
sb. a dun horse; Proverb: Dun is in the myre
Dunne, adj. dun, dull brownVariants: donneEtymology: Anglo-Saxon dunn; Old Irish donn, dond (Windisch).
to solicit payment.—Old Cant, from the French donnez , give; or from Joe Din , or Dun , a famous bailiff; or simply a corruption of din , from the Anglo-Saxon  dunan , to clamour.

An importunate creditor. Dunny, in the provincial dialect of several counties, signifies DEAF; to dun, then, perhaps may mean to deafen with importunate demands: some derive it from the word DONNEZ, which signifies GIVE. But the true original meaning of the word, owes its birth to one Joe Dun, a famous bailiff of the town of Lincoln, so extremely active, and so dexterous in his business, that it became a proverb, when a man refused to pay, Why do not you DUN him? that is, Why do not you set Dun to attest him? Hence it became a cant word, and is now as old as since the days of Henry VII. Dun was also the general name for the hangman, before that of Jack Ketch.

      And presently a halter got,
      Made of the best strong hempen teer,
      And ere a cat could lick her ear,
      Had tied it up with as much art,
      As DUN himself could do for's heart.
      Cotton's Virgil Trav. book iv.