The sixth article's going through (3)
I believe the answer is:
via
'going through' is the definition.
(via means through)
'the sixth article's' is the wordplay.
'the sixth' becomes 'vi' (Roman numerals).
'article' becomes 'a' (the indefinite article in English).
'vi'+'a'='VIA'
(Other definitions for via that I've seen before include "Passing through" , "By way of - in Latin" , "Roman road" , "A Roman way" , "By means of" .)