Found out, Eddy coloured (4)
I believe the answer is:
dyed
'coloured' is the definition.
(dyeing is a kind of colouring)
'found out eddy' is the wordplay.
'found out' indicates anagramming the letters (discovered out of the normal letter order).
'eddy' anagrammed gives 'DYED'.
(Other definitions for dyed that I've seen before include "not natural?" , "(Of fabric) coloured" , "Tinted" , "Stained - coloured" , "Re-coloured" .)