Piece of news I encountered on return (4)
I believe the answer is:
item
'piece of news' is the definition.
(I've seen this before)
'i encountered on return' is the wordplay.
'encountered' becomes 'met' ('meet' can be a synonym of 'encounter').
'on return' says the letters should be written in reverse.
'met' backwards is 'tem'.
'i'+'tem'='ITEM'
(Other definitions for item that I've seen before include "Piece in paper" , "Two lovers as one" , "A thing or unit" , "Report" , "partners" .)