Heir of resonance (3)
I believe the answer is:
son
'heir' is the definition.
(I've seen this in another clue)
'of resonance' is the wordplay.
'of' says the answer is hidden in the clue.
'SON' is hidden within 'resonance'.
(Other definitions for son that I've seen before include "Human offspring" , "A relative" , "Male child" , "Male scion" , "Native" .)