Nearly all ancient works associated with a stink (9)
I believe the answer is:
olfactory
'associated with a stink' is the definition.
(I've seen this before)
'nearly all ancient works' is the wordplay.
'nearly all' means to remove the last letter.
'ancient' becomes 'old' ('old' can be similar in meaning to 'ancient').
'works' becomes 'factory' (factory is a kind of works**).
'old' with its last letter removed is 'ol'.
'ol'+'factory'='OLFACTORY'
(Other definitions for olfactory that I've seen before include "associated with a stink" , "concerned with smell" , "Pertaining to the sense of smell" , "Dealing with smells" , "Smelling" .)