For each opera has it (3)
I believe the answer is:
per
'for each' is the definition.
(per person)
'opera has it' is the wordplay.
'has it' indicates a hidden word.
'PER' is hidden in the letters of 'opera'.
(Other definitions for per that I've seen before include "Preposition meaning for each" , "Preposition indicating by means of" , "For each or every" , "According to" .)