The cry a chap makes out of love! (4)
I believe the answer is:
moan
'the cry' is the definition.
(thesaurus)
'a chap makes out of love' is the wordplay.
'a chap makes' becomes 'man' (I can't justify this - if you can you should give a lot more credence to this answer).
'out of' indicates putting letters inside.
'love' becomes 'o' (In tennis, 'love' means 'zero').
'man' enclosing 'o' is 'MOAN'.
Can you help me to learn more?
(Other definitions for moan that I've seen before include "bellyache" , "Complain mournfully" , "Bewail" , "Complain; mournful sound" , "Lament; grumble" .)