Boy, I see, of sound nature (5)
I believe the answer is:
sonic
'sound nature' is the definition.
'sonic' can be an answer for 'sound' (sonic means relating to sound). I'm not sure about the 'nature' bit.
'boy i see' is the wordplay.
'boy' becomes 'son' (male child).
'see' becomes 'C' (the word for the letter, according to Chambers).
'son'+'i'+'c'='SONIC'
'of' is the link.
Can you help me to learn more?
(Other definitions for sonic that I've seen before include "seven hundred and forty three mph!" , "Employing sound" , "Boom of jet aircraft" , "Sort of boom" , "Producing sound" .)