n. 1 victor, winner, conqueror, title-holder, prizewinner, titleist She is the women's singles champion for the fourth year in a row 2 defender, guardian, protector, hero, supporter, backer, protagonist, advocate He acquired a reputation as champion of the low-paid 3 fighter, combatant, hero, warrior, campaigner, veteran A stouter champion never handled a sword The boar is often regarded as the champion among beasts.
v. 4 defend, protect, guard; support, back, stand up for, fight for, maintain, sustain, uphold; espouse, forward, promote, advocate He has always championed the cause of the underdog