›treating someone in a way that is right or reasonable, or treating people equally and not allowing personal opinions to influence your judgment: All he asks is a fair chance to prove his innocence.I’m willing to do my fair share of the work (= equal part).›If a game or competition is fair, it is done according to the rules: It was a fair fight.›In some sports, esp. baseball, fair means within the playing field: The umpire ruled it a fair ball.