I assembled returned article (4)
I believe the answer is:
item
'article' is the definition.
(thesaurus)
'i assembled returned' is the wordplay.
'assembled' becomes 'met' ('meet' can be a synonym of 'assemble').
'returned' is a reversal indicator.
'met' backwards is 'tem'.
'i'+'tem'='ITEM'
(Other definitions for item that I've seen before include "Matter" , "Two people widely seen as one?" , "A single piece of information" , "Also no more" , "Separate object or unit" .)