ˌmarginal ˈrate ( ˈmarginal ˈrate of ˈtax, ˌmarginal ˈtax rate)
noun
[] () a rate of tax that is paid on your next unit of income; the highest rate of tax that sb pays边际税率◆The government has promised to lower marginal rates.政府承诺下调边际税率。◆I've stopped doing freelance work as my marginal tax rate on it was more than 50%.我已经不再从事自由职业，因为我在这项工作上的边际税率超过 50%。