Crossword Genius

Blue feathers (4)

Ross

I believe the answer is:

I believe this clue is a double definition.

'blue' is the first definition.
(I've seen this before)

'feathers' is the second definition.
(down is a kind of feathers)

(Other definitions for down that I've seen before include "Not working (computer)", "Rolling hill; soft feathers", "Depressed; swallow", "when in adversity", "In a low mood; hill".)

I've seen this clue in Mirror.