灰土

はいつち
ashes and earth
poor volcanic soil

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かいど【灰土】

〔灰と土〕 earth and ash(es).

●灰土に帰す[と化す] be utterly destroyed; be reduced [burnt] to ashes

・戦火で町は灰土に帰した[と化した]. The town was burnt to ashes in the war.