The slangy spelling “ruff” for “rough” is not appropriate in formal writing, but your spelling-checker won’t flag it because “ruff” has a traditional meaning of its own, denoting a frilled collar.
This is the ten-year anniversary 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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