Business in orchestra deafening (5)
I believe the answer is:
trade
'business' is the definition.
(I know that trade is a type of business)
'in orchestra deafening' is the wordplay.
'in' indicates the answer is hidden within the clue.
'TRADE' is hidden within 'orchestra deafening'.
(Other definitions for trade that I've seen before include "Commerce - traffic" , "A skilled craft to earn living" , "Barter or swap" , "Calling" , "Give and receive (blows)" .)