Where does “ข้อสอบ” come from?

ข้อสอบ (Thai) comes from Thai ข้อ, from Proto-Tai χoːᶜ — joint.

ข้อสอบ (Thai): examination question; examination paper; test

Definitions

  1. examination question; examination paper; test

Ancestry of “ข้อสอบ”, step by step

ข้อสอบ traces back through two separate lines of ancestry.

via Thai ข้อ

StepLanguageWordMeaning
1Thaiข้อjoint
2Proto-Taiχoːᶜjoint

via Thai สอบ

StepLanguageWordMeaning
1Thaiสอบto examine; to subject to an examination or test;...
Every word from Proto-Tai χoːᶜ →Every word from Thai ข้อ →