tax deduction

lessening the income tax taken from individuals

A tax deduction or a tax-deductible expense represents an expense incurred by a taxpayer that is subtracted from gross income and results in a lower overall taxable income.In everyday terms, this means that tax-deductibility increases a person's purchasing power (if the person is paying taxes), by "adding money" to the purchase that would have otherwise gone to taxes.As a simplified example, if we assume someone has a flat tax rate of 33 nd is paying taxes, they can buy something for $600 that is not tax-deductible, or something for $900 that is, and have just as much money left over. This is because the $600 represents the same $900 in earnings, but after taxes have been paid on it. However, the simplification (a flat rate of 33% taxes) does not describe the U.S. tax system in most circumstances.
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Noun
1. a reduction in the gross amount on which a tax is calculated; reduces taxes by the percentage fixed for the taxpayer's income bracket
(synonym) tax write-off, deduction
(hypernym) write-off, write-down
(hyponym) tax benefit, tax break

An expense which a taxpayer is allowed to deduct from taxable income.