Group of musicians for topless clubs breaking hearts (9)
I believe the answer is:
orchestra
'group of musicians' is the definition.
(I've seen this before)
'for topless clubs breaking hearts' is the wordplay.
'topless' means to remove the first letter.
'clubs' becomes 'c' (abbreviation used in card games such as bridge).
'breaking' indicates an anagram.
'for' with its initial letter removed is 'or'.
'hearts' anagrammed gives 'hestra'.
'or'+'c'+'hestra'='ORCHESTRA'
(Other definitions for orchestra that I've seen before include "Brass, woodwind, strings and percussion" , "Musical ensemble" , "Gamelan, for instance" , "Other cars (anag.)" , "Large group of players" .)