United came out on top, we’re told (3)
I believe the answer is:
one
'united' is the definition.
(as in a phrase like 'we are one')
'came out on top we're told' is the wordplay.
'came out on top' becomes 'won' (I've seen this in another clue).
'we're told' indicates a 'sounds like' (homophone) clue.
'won' is a homophone of 'ONE'.
(Other definitions for one that I've seen before include "SECOND PART OF 16" , "Single and undivided" , "time" , "I can mean this" , "joke" .)