前者指的是人，后者指的是地位，称号


champion
n.[C]
1. (竞赛的)优胜者,冠军
2. 出类拔萃的人(或物)
He is a champion at writing familiar essays.
他是写小品文的好手。
3. 提倡者,拥护者;战士,斗士[(+of)]
He is a champion of equal opportunities for all races.
他是一个为各种族机会均等而奋斗的人。
vt.
1. 拥护,支持,为...而战
She championed the cause of civil rights.
她积极支持民权运动。
a.
1. 优胜的,冠军的
That state has brought forth two champion boxers.
那个州出了两名得冠军的拳击手。
2. 【口】第一流的
ad.
1. 【英】【口】极好地,以第一流水平

championship
n.
1. 冠军的地位,冠军称号[C]
Susan won the spelling championship.
苏珊在拼字比赛中得了第一名。
2. 锦标赛[P1]
the World Women's Volleyball Championships
世界女子排球锦标赛
3. 拥护,支持;提倡[U][(+of)]
His championship of women's rights is well known.
他提倡女权是众所周知的。