What is Tax Deduction?

Legal Definition
Tax deduction is a reduction of income that is able to be taxed, and is commonly a result of expenses, particularly those incurred to produce additional income. The difference between deductions, exemptions and credit is that deductions and exemptions both reduce taxable income, while credits reduce tax.
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Legal Definition
The fixed percentage or amount that tax authorities allow a tax payer to subtract from the adjusted gross income to get to the taxable income.
Legal Definition
a term that is used to describe the expenses that are deductible from a person's income taxes.