adjective / noun
dun
DUN/dʌn/
A dull grayish-brown color.
The wool scarf is a muted dun.

Etymology
Old English dunn covered both dingy brown and dark coloring. The selected sense preserves the brown part of that range, describing a dull shade tinged with gray.
In context
… his watery eyes that seemed almost of the same color as the dun white sockets …
More examples
- A dun hillside stretched beyond the road.
- She mixed a dull dun for the background.
- The fabric was a muted dun.
Forms
dun