斎
サイ, とき, つつし.む, ものいみ, い.む, いわ.う, いつ.く, いつき, さえ, ひとし, いつ, きよ, ただ, とき, よし

purification, Buddhist food, room, worship, avoid, alike

JLPT1 G7 S11 F1155

As per 齊# (align) + 示 altar/the supernatural → align body and spirit through fasting and other purification methods → *purification* → *room* (for abstinence, training or study).

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