Robber one featured in article on forgery primarily (5)
I believe the answer is:
thief
'robber' is the definition.
(both can mean someone who steals)
'one featured in article on forgery primarily' is the wordplay.
'one' becomes 'i' (Roman numeral).
'featured in' means one lot of letters goes inside another.
'article' becomes 'the' (the definite article).
'on' says to put letters next to each other.
'primarily' suggests taking the first letters.
The initial letter of 'forgery' is 'f'.
'i' placed into 'the' is 'thie'.
'thie'+'f'='THIEF'
(Other definitions for thief that I've seen before include "'Taffy was a - - '" , "A robber or pickpocket" , "nicker?" , "Larcenist" , "Burglar, say" .)