exemption

nouns

immunity from an obligation or duty
exemption, freedom
is derived from
exempt
a deduction allowed to a taxpayer because of his status (having certain dependents or being blind or being over 65 etc.)
"additional exemptions are allowed for each dependent"
exemption
is a type of (narrower)
a reduction in the gross amount on which a tax is calculated; reduces taxes by the percentage fixed for the taxpayer's income bracket
deduction, tax deduction, tax write-off
an act exempting someone
"he was granted immunity from prosecution"
exemption, granting immunity, immunity