Plant imbued with gold colour (5)
I believe the answer is:
ivory
'colour' is the definition.
(ivory is a kind of colour)
'plant imbued with gold' is the wordplay.
'plant' becomes 'ivy' (ivy is a plant).
'imbued with' indicates putting letters inside.
'gold' becomes 'or' ('or' is the heraldic name for gold).
'ivy' going around 'or' is 'IVORY'.
(Other definitions for ivory that I've seen before include "Piano key" , "Substance of elephant's tusk" , "Off-white colour" , "Yellowish white - material from tusks" , "Some hunt this" .)