Way of addressing a man in business I respect (3)
I believe the answer is:
sir
'way of addressing a man' is the definition.
(respectful address for a man)
'in business i respect' is the wordplay.
'in' says the answer is hidden in the clue.
'SIR' is hidden in the letters of 'business i respect'.
(Other definitions for sir that I've seen before include "Polite form of address to a man" , "address to teacher" , "Title of 1 across" , "Polite or formal address to male" , "Term of address for a gentleman" .)