Article I encountered on the way back (4)
I believe the answer is:
item
'article' is the definition.
(I've seen this before)
'i encountered on the way back' is the wordplay.
'encountered' becomes 'met' ('meet' can be a synonym of 'encounter').
'on the way back' says the letters should be written backwards.
'met' back-to-front is 'tem'.
'i'+'tem'='ITEM'
(Other definitions for item that I've seen before include "A thing or unit" , "Single unit" , "Article, object" , "Bit of news to broadcast" , "Whole individual unit" .)