Object of writing (7)
I believe the answer is:
article
I believe this is a double definition.
'object' is the first definition.
'writing' is the second definition.
(article is a kind of writing)
'of' acts as a link.
(Other definitions for article that I've seen before include "account in the Financial Times" , "Eg, a, an or the" , "Division" , "something" , "Object - piece of writing" .)