tax evasion

n. avoidance of paying taxes, not reporting income

Tax avoidance is the legal utilization of the tax regime to one's own advantage, in order to reduce the amount of tax that is payable by means that are within the law. Tax avoiders attempt to prepare their income and wealth statement either to attract a lower rate of taxes and/or to narrow the tax base which is to be used for assessing leviable taxes. Tax avoiders resort to loophole in the law that allows them to lessen the amount of taxes leviable on them and hence, they cannot be charged within the framework of law for evading taxes due to the public exchequer.
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Noun
1. the deliberate failure to pay taxes (usually by making a false report)
(hypernym) evasion, nonpayment

An illegal strategy to decrease tax burden by underreporting income, overstating deductions, or using illegal tax shelters.

A prohibited or illegal act or omission which is designed to reduce a person’s tax liability. - (read more on Tax Evasion)