Not natural, in a way (4)
'not natural in a way' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for dyed that I've seen before include "Stained - coloured" , "Stained with a new colour" , "Re-coloured" , "(Of fabric) coloured" , "Imbued with artificual colour" .)
(Other definitions for posed that I've seen before include "Sat (for artist)" , "Presented (a question)" , "Assumed" , "Struck attitude, perhaps for painter" , "Struck attitude - sat for painter" .)