One article is primarily targeting non-believer (7)
I believe the answer is:
atheist
'non-believer' is the definition.
(someone who doesn't believe in God)
'one article is primarily targeting' is the wordplay.
'one' becomes 'a' (a thing is one thing).
'article' becomes 'the' (the definite article).
'primarily' says to take the initial letters.
The initial letter of 'targeting' is 't'.
'a'+'the'+'is'+'t'='ATHEIST'
(Other definitions for atheist that I've seen before include "Sceptic" , "One denies the existence of a god" , "Unbeliever" , "One disbelieving in the existence of God or gods" , "One who does not believe in the existence of a god" .)