Champion (4)
'champion' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for victor that I've seen before include "Competitor who's first" , "The one who wins the battle" , "Oh dear!" , "The . . . . . . comic with Alf Tupper" , "One coming out on top" .)
'champion' is the definition.
(winner of a competition)
This is all the clue.
(Other definitions for winner that I've seen before include "Conqueror" , "film director" , "One that came first" , "The champ" , "Top player" .)
'champion' is the definition.
(advocate can mean to champion or support)
This is all the clue.
(Other definitions for advocate that I've seen before include "barman" , "Person who pleads on behalf of another, like barrister" , "Recommend like counsellor?" , "Caveat, do about lawyer in court" , "Public supporter" .)
'champion' is the definition.
(thesaurus)
This is all the clue.
(Other definitions for exponent that I've seen before include "Skilled performer" , "Interpreter - performer" , "Interpretive artist or performer" , "Propagandist" , "Interpreter, advocate; (maths.) power" .)
'champion' is the definition.
(I know that champion can be written as hero)
This is all the clue.
(Other definitions for hero that I've seen before include "Leander's suitor" , "Principal character in a film or novel" , "Valiant man" , "priestess of Aphrodite" , "Exceptionally brave person" .)