Label left on a musical instrument (5)
I believe the answer is:
tabla
'musical instrument' is the definition.
(I've seen this before)
'label left on a' is the wordplay.
'label' becomes 'tab' (I've seen this in another clue).
'left' becomes 'l' (common abbreviation).
'on' means one lot of letters go next to another.
'tab'+'l'+'a'='TABLA'
(Other definitions for tabla that I've seen before include "Indian musical instrument" , "Pair of drums used in Indian music" , "percussion instrument" , "set of drums" , "one battered by Indians" .)