He was chosen as the best-looking employee in the company.

best-looking 是由形容词 best（最好的）和现在分词 looking（看起来）组成的复合形容词，best 是 good 的最高级形式，looking 来自动词 look（看、看起来）。best-looking 合起来表示"外貌最出众的、最好看的"。