"同龄人"的英文是 "peer"。它来源于中世纪拉丁文中的 "par" 或 "paris"，意为 "等价物"或"平等者"。在英文中，"peer" 指的是与某人年龄相仿的人。

例句：

She always feels shy around her peers.（她总是在同龄人面前感到害羞。）

He has a lot in common with his peers.（他和同龄人有很多共同点。）

She is very popular among her peers.（她在同龄人中很受欢迎。）