I believe it should say "married but withhold at higher single rate"but you may want to double check with your HR to confirm. It is perfectly acceptable to indicate on your W4 to withhold as Single if you wish. And with no exemptions, either, if you want, and still file your income tax with your actual married status. People often do this to try to be sure that enough is withheld. Your W-4 only affects how much money your employer withholds in taxes from your pay. It does not control your choices as to filing your tax return.
