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subtraction; deduction (e.g. of tax)
確定申告で医療費控除を申請して税金を減らした。
I applied for a medical expense deduction.
各種控除を受けると課税所得が減り税金が安くなる。
You pay less tax if you get deductions.
子供がいるので扶養控除について税理士に調べてもらった。
Since I have children, I had a tax accountant look into dependent deductions for me.