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to dust; to remove dust
to slap; to hit (with the palm)
to use up money
「叩く」 has another reading with different meanings.
埃をはたいて服を綺麗にした。
I dusted off the clothes.
怒りに任せて彼女は子の頬をはたきかけたが、寸前で手を止め、深く息を吐いた。
Carried away by anger, she nearly slapped her child's cheek, but stopped her hand at the last moment and let out a deep breath.
玄関に置いてあった座布団を外で叩いた。
I dusted the cushion that was in the entryway outside.