top dog 头号人物；(尤指竞争中的)夺魁者；优胜者

【例句】
Again she struggled with it, fighting him with her small, fine eyes, with the plush arrogance of a top dog, with her nascent transference to another man, with the accumulated resentment of years.
她再次对他的才智进行反抗，用她细巧秀丽的眼睛，用一个优胜者极度的傲慢，用她刚萌生的移情别恋，用积累多年的怨愤同他较量。

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。