ヨウ, つね, のぶ, やす
commonplace, ordinary, employment
JLPT1 G7 S11 F2038
用# use + an abbreviated form of 庚 (firm stem) → *use* a stem or similar *ordinary* tool in performing routine *work* (such as constructing an earthen wall; compare 墉) → *common* (← ordinary) → *mediocre*. "Employee" and "reward" are borrowed meanings (compare 傭).
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