Days-old (5)
I believe the answer is:
stale
'days-old' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for stale that I've seen before include "Mouldy or hackneyed" , "no longer bearing interest?" , "Least (anag.)" , "Not fresh, being least" , "Musty or hackneyed" .)