What the continent won't need returned to the west (6)
I believe the answer is:
diaper
'what the continent won't need' is the definition.
(incontinent people might need diapers)
'returned to the west' is the wordplay.
'returned' becomes 'repaid' ('repay' can be a synonym of 'return').
'to the west' says the letters should be written in reverse (letters written right to left or 'east to west').
'repaid' reversed gives 'DIAPER'.
(Other definitions for diaper that I've seen before include "Baby's nappy" , "type of paving" , "An American nappy" .)