Belly, more formally (7)
I believe the answer is:
abdomen
'belly more formally' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for abdomen that I've seen before include "corporation's site" , "Part of the body below chest and diaphragm" , "Ban demo (anag)" , "Tummy" , "Central region" .)