Unhappy people reformed by a sermon (7)
I believe the answer is:
moaners
'unhappy people' is the definition.
The definition and answer can be both people as well as being plural nouns.
Perhaps there's a link between them I don't understand?
'reformed by a sermon' is the wordplay.
'reformed' indicates an anagram.
'by' means one lot of letters go next to another.
'a' after 'sermon' is 'sermona'.
'sermona' with letters rearranged gives 'MOANERS'.
Can you help me to learn more?
(Another definition for moaners that I've seen is " People crying".)