Cure using colour (4)
I believe the answer is:
ecru
'colour' is the definition.
(ecru is a kind of colour)
'cure using' is the wordplay.
'using' indicates an anagram (the letters used in a different way).
'cure' is an anagram of 'ECRU'.
(Other definitions for ecru that I've seen before include "Very light brown colour" , "Colour of unbleached linen" , "Greyish-yellow colour" , "Neutral colour" , "Natural stuff" .)