Horrify a friend, being soft-hearted (5)
I believe the answer is:
appal
'horrify' is the definition.
(I know that horrify can be written as appal)
'a friend being soft-hearted' is the wordplay.
I cannot really understand how this works, but
'a' is within the answer.
'friend' could be 'pal' (pal can mean a friend) and 'pal' is found within the answer.
'soft' could be 'p' (musical abbreviation for 'piano') and 'p' is found in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for appal that I've seen before include "Scandalise" , "Put at rest (suspicion)" , "expressed dismay" , "To shock, dismay" , "Shock, horrify" .)