scotch free/scot free
Getting away with something “scot free” has nothing to do with the Scots (or Scotch). The scot was a medieval tax; if you evaded paying it you got off scot free. Some people wrongly suppose this phrase alludes to Dred Scott, the American slave who unsuccessfully sued for his freedom. The phrase is “scot free”: no H, one T.
Blue moons are not just for Kentucky. In episode #5 of the Common Errors in English Usage podcast, Paul Brians discusses the origin of "Once in a blue moon."
This is the tenth year of the Common Errors in English Usage calendar. To celebrate, we are bringing back some of our favorite interesting, funny, but sometimes merely silly entries through the years before going on hiatus in 2016.
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