Dictionary definition · champion
noun
- someone who has won first place in a competition
- someone who fights for a cause
- a person who backs a politician or a team etc."all their supporters came out for the game"
- someone who is dazzlingly skilled in any field
verb
- protect or fight for as a champion
adjective
- holding first place in a contest"a champion show dog"
Source: Open English WordNet (CC BY 4.0).