Lovely-sounding honey really horrible (9)
I believe the answer is:
melodious
'lovely-sounding' is the definition.
I can't judge whether this defines the answer.
'honey really horrible' is the wordplay.
'honey' becomes 'mel' (Latin name for honey).
'really horrible' becomes 'odious' (I can't justify this - if you can you should believe this answer much more).
'mel'+'odious'='MELODIOUS'
Can you help me to learn more?
(Other definitions for melodious that I've seen before include "music to the ears!" , "Tuneful" , "Sweet'" .)