Nouns

(n)champion, champ, title-holdersomeone who has won first place in a competition
(n)champion, fighter, hero, paladinsomeone who fights for a cause
(n)supporter, protagonist, champion, admirer, booster, frienda person who backs a politician or a team etc.“all their supporters came out for the game”, “they are friends of the library”
(n)ace, adept, champion, sensation, maven, mavin, virtuoso, genius, hotshot, star, superstar, whiz, whizz, wizard, wizsomeone who is dazzlingly skilled in any field

Verbs

(v)champion, defendprotect or fight for as a champion

Adjectives

(s)champion, prizewinningholding first place in a contest“a champion show dog”, “a prizewinning wine”