Southern corporation holds party in this private space (7)
I believe the answer is:
sanctum
'space' is the definition.
(I have seen 'sacred space' mean 'sanctum' so perhaps 'space' could also mean 'sanctum')
'southern corporation holds party in this private' is the wordplay.
'southern' becomes 's' (abbreviation).
'corporation' becomes 'tum' ('corporation' is a humorous term for stomach fat).
'holds' indicates putting letters inside.
'party in this private' becomes 'anc' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
's'+'tum'='stum'
'stum' going around 'anc' is 'SANCTUM'.
Can you help me to learn more?
(Other definitions for sanctum that I've seen before include "A person's private room, often inner" , "Inviolable retreat" , "Sacred area" , "Private/sacred place" , "Sacred or safe place" .)