Wonderful / shattering (8)
I believe the answer is:
smashing
I believe this clue is a double definition.
'wonderful' is the first definition.
(I've seen this in another clue)
'shattering' is the second definition.
(I know that shattering can be written as smashing)
(Other definitions for smashing that I've seen before include "Breaking violently into pieces" , "2 [COOL] or 3 [DANDY] perhaps, possibly 20d [WICKED] or 22 [GEAR] !" , "Wonderful" , "use for plates at a Greek wedding?" , "Excellent; breaking" .)