He didn't sleep well last night, and his eyes were red-rimmed this morning.

red-rimmed 是由形容词 red（红色的）和名词 rim（边缘）加上连字符和-ed后缀组成的复合形容词。rim 指"边缘"，-ed 后缀表示"具有...特征的"。 red-rimmed 字面意思是"边缘发红的"，用来形容眼睛因疲劳或哭泣而发红的样子。