[mass noun] An additional tax on something already taxed.
- ‘To many country-house owners, it seemed that GütterdÜmmerung had arrived, and their way of life was being swept away in a flood of supertax and crippling fuel bills.’
- ‘And he would impose progressive supertaxes upon valuable mineral, timber, and water power holdings, and upon certain agricultural lands not cultivated by the owners.’
- ‘They were unlikely to get the chance, with supertax at almost 100%.’
- ‘He decided to introduce a British-style graduated income tax on unearned income from rent and interest, profits, and earned income, with supertax on incomes over 5,000 francs.’