Dressing musicians, no spring chickens (9)
I believe the answer is:
bandaging
'dressing' is the definition.
(bandaging is a kind of dressing)
'musicians no spring chickens' is the wordplay.
'musicians' becomes 'band' (I've seen this before).
'no spring chickens' becomes 'aging' (someone who is 'no spring chicken' is old).
'band'+'aging'='BANDAGING'
(Other definitions for bandaging that I've seen before include "some first aid" , "Providing cover" , "holding together" .)