To take something for oneself; to appropriate something that belongs to others.
将别人的东西拿来作为自己的。
明·李开先《宝剑记》第二十四出先从片进，累建大功，童贯占为己有欺瞒皇上。”
He tried to keep the found money for himself.
Learn the next connected idiom: 据为己有 (jù wéi jǐ yǒu) → 有条不紊 (yǒu tiáo bù wěn)
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