Field of interest that isn’t quiet the real one (5)
I believe the answer is:
realm
'field of interest that isn't quiet' is the definition.
'realm' can be an answer for 'field of interest' (I've seen this before). I am unsure of the rest of the definition.
'the real one' is the wordplay.
'one' becomes 'm' (I can't explain this - if you can you should believe this answer much more).
'real'+'m'='REALM'
Can you help me to learn more?
(Other definitions for realm that I've seen before include "Peers are possessed by this" , "where ruler holds sway?" , "World" , "Area of knowledge under discussion" , "Dominion" .)