Where does “若” come from?

若 (Chinese) comes from Proto-Sino-Tibetan na-ŋ — you.

Ancestry of “若”, step by step

若 traces back through two separate lines of ancestry.

via Proto-Sino-Tibetan na-ŋ

StepLanguageWordMeaning
1Proto-Sino-Tibetanna-ŋyou

via Chinese 如

StepLanguageWordMeaning
1Chinese如—
Every word from Proto-Sino-Tibetan na-ŋ →