Ronald to perform musical work (5)
I believe the answer is:
rondo
'musical work' is the definition.
(I've seen this before)
'ronald to perform' is the wordplay.
'ronald' becomes 'ron' (I've seen this in other clues).
'to perform' becomes 'do' ('do' can be a synonym of 'perform').
'ron'+'do'='RONDO'
(Other definitions for rondo that I've seen before include "Musical work" , "Musical piece with a recurring theme" , "Donor (anag) - piece of music" , "noted work" , "Musical form with recurrent theme" .)