Fat stomach, and firm (11)
I believe the answer is:
corporation
I believe this clue is a triple definition!
'fat' is the first definition.
(I know that corporation is a type of belly)
'stomach' is the second definition.
(I've seen this before)
'and' is a link.
'firm' is the third definition.
(I know that corporation is a type of firm)
(Other definitions for corporation that I've seen before include "Big firm" , "Large firm" , "Large company" , "belly" , "beer gut" .)