Where does “สือ” come from?

สือ (Thai) comes from Proto-Tai sɯːᴬ, from Middle Chinese 書.

สือ (Thai): letter; character; book

Definitions

letter; character; book

Ancestry of “สือ”, step by step

Step	Language	Word	Meaning
1	Proto-Tai	sɯːᴬ	writing; book
2	Middle Chinese	書	—

Words derived from “สือ”

Every word from Middle Chinese 書 →

สือ — Etymology, Origin & Word History | Etymology Explorer