Green decor centrally sound (10)
I believe the answer is:
ecological
'green' is the definition.
(I've seen this before)
'decor centrally sound' is the wordplay.
'centrally' indicates the central letters.
'sound' becomes 'logical' (I've seen this in another clue).
The centre of 'decor' is 'eco'.
'eco'+'logical'='ECOLOGICAL'
(Other definitions for ecological that I've seen before include "Gaelic cool (anag.)" , "Green" .)