Word Study
supertax
CIDE DICTIONARY
supertax, n. [Super- + tax.].
A tax in addition to the usual or normal tax; specif., in the United Kingdom, an income tax of sixpence for every pound in addition to the normal income tax of one shilling and twopence for every pound, imposed, by the Finance Act of 1909-1910 (c. 8, ss 66, 72), on the amount by which the income of any person exceeds Webster 1913 Suppl.]
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