What does "dun" mean?

Dun: One who duns; a dunner. To be pulled by the sleeve by some rascally dun. Arbuthnot.

Additional senses

  1. 2.An urgent request or demand of payment; as, he sent his debtor a dun.
  2. 3.Of a dark color; of a color partaking of a brown and black; of a dull brown color; swarthy. Summer's dun cloud comes thundering up. Pierpont. Chill and dun Falls on the moor the brief November day. Keble. Dun crow (Zoöl.), the hooded crow; -- so called from its color; -- also called hoody, and hoddy. -- Dun diver (Zoöl.), the goosander or merganser.

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