Promotional body’s tune is revised to accommodate singer (9)
I believe the answer is:
institute
'promotional body's tune is revised to accommodate singer' is the definition.
I can't judge whether this defines the answer.
'tune is revised to accommodate singer' is the wordplay.
'revised' indicates anagramming the letters.
'to accommodate' indicates putting letters inside.
'singer' becomes 'tit' (type of songbird).
'tune'+'is'='tuneis'
'tuneis' with letters rearranged gives 'insute'.
'insute' placed around 'tit' is 'INSTITUTE'.
Can you help me to learn more?
(Other definitions for institute that I've seen before include "Start - school" , "college" , "Begin (legal proceedings)" , "Scientific, educational or social organisation" , "Establish - seat of learning" .)