Declines in standards (5)
I believe the answer is:
flags
I believe this clue is a double definition.
'declines' is the first definition.
(I've seen this before)
'standards' is the second definition.
(I know this)
'in' acts as a link.
(Other definitions for flags that I've seen before include "Tires; national symbols" , "Paving stones" , "Droops" , "Grows languid" , "Banners" .)