悔
カイ, く.いる, く.やむ, くや.しい

repent, regret

JLPT1 G7 S9 F1460

As per 毎# (dark) + 心 heart/emotions → dark emotions, in the form of *regret* or *vexation* → *repent*; *mourn* → *mortifying*; *condolences*.

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