纳闷儿
nàmènr · HSK 7
puzzled
😕 纳 take-in + 闷 stuffy = a stuffy feeling taken inside leaves you puzzled; -儿 is erhua
闷 — door 門 + heart 心
A semantic compound: 心 (heart) enclosed by 門 (door) depicts a heart shut behind a closed door, evoking stuffiness and depression. Read mēn it means stuffy or airless; read mèn it means bored, depressed, or sealed up tight.