Eddy, possibly, changed colour (4)
I believe the answer is:
dyed
'changed colour' is the definition.
(I've seen this before)
'eddy possibly' is the wordplay.
'possibly' is an anagram indicator.
'eddy' is an anagram of 'DYED'.
(Other definitions for dyed that I've seen before include "Coloured by dipping in liquid" , "not natural?" , "Artificially coloured" , "Stained - coloured" , "(Of fabric) coloured" .)