Sneer, making the girl's dad blow his top! (9)
I believe the answer is:
disparage
'sneer' is the definition.
(thesaurus)
'the girl's dad blow his top' is the wordplay.
I cannot quite understand how this works, but
'girl's' could be 'dis' (Di is short for Diana) and 'dis' is present in the answer.
'dad' could be 'pa' (synonyms) and 'pa' is located in the answer.
The remaining letters 'rage' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'making' acts as a link.
Can you help me to learn more?
(Other definitions for disparage that I've seen before include "Run down" , "I grasped a change to belittle" , "Belittled" , "Slight" , "Scorn" .)