It's not true it comes to a moral conclusion (5)
I believe the answer is:
fable
This could be a double definition.
'it's not true' is the first definition.
(I've seen this before)
'it comes to a moral conclusion' is the second definition.
The definition suggests a singular noun which matches the answer.
Can you help me to learn more?
(Other definitions for fable that I've seen before include "Moral tale" , "Story, often with moral" , "Aesop story" , "It's not true" , "One of Aesop's tales" .)