Horse and cart ordered for musical group (9)
I believe the answer is:
orchestra
'for musical group' is the definition.
(orchestra is a kind of musical group)
'horse and cart ordered' is the wordplay.
'and' is a charade indicator (letters next to each other).
'ordered' indicates an anagram.
'horse' after 'cart' is 'carthorse'.
'carthorse' is an anagram of 'ORCHESTRA'.
(Other definitions for orchestra that I've seen before include "Ensemble of players" , "Theatre area for musicians" , "Large group of instrumentalists" , "Noted performers" , "Large band of musicians" .)