top dog (尤指竞争中的)夺魁者，优胜者，头儿

【例句】
After winning four major international events he's the top dog among formula one motor racing drivers.
在赢得了4次重大国际比赛的冠军后,他又在工作容为1500-3000cm3的赛车比赛中成为优胜者。

I don't want to be the top dog at our company. I just do my job as well as I can.
我不想成为我们公司的佼佼者，我只是尽我所能做好我的工作。