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empty; vacant; hollow
財布の中が空っぽでお金が一円もなかったよ。
My wallet was empty and I didn't have a single yen.
冷蔵庫が空っぽなので買い物に行かなければ。
The refrigerator is empty, so I have to go shopping.
頭が空っぽになるまで疲れて何も考えられない。
I'm so tired my head is empty and I can't think.