Old fir might be very ornate (6)
I believe the answer is:
florid
'very ornate' is the definition.
(I've seen this in another clue)
'old fir might be' is the wordplay.
'might be' is an anagram indicator.
'old'+'fir'='oldfir'
'oldfir' with letters rearranged gives 'FLORID'.
(Other definitions for florid that I've seen before include "Elaborately intricate" , "(Of language) flowery" , "Over-elaborate" , "Flushed with red" , "Ruddy in appearance" .)