コウ, キョウ, めん
exam, school, printing, proof, correction
JLPT5 G1 S10 F294
As per 交# (twist/cross) + 木 tree/wood → wooden *cross fetters* or *shackles*. Also, *fence* (← construction of crossed boards). *School* is from the idea of a place where an exchange of teaching and learning (by comparison) is performed; the same notion is at work in 學. For shackles/fetters, compare 械, 枷, 絆 and 桎.
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