I found a book titled 100 Words Almost Everyone Mixes Up or Mangles (Houghton Mifflin Harcourt, from the editors of the American Heritage Dictionaries). Having a fondness for trivia, I bought the book. The words listed were all familiar to me. I was about to congratulate myself on paying attention in school when I reached the section on “slew”, “slough”, and “slue”.
Slew, a verb or a noun, comes from either Old Irish or Old English, depending on its definition. It is also a variant of both slough and slue. Slough is either from Old English or Middle English/Middle High German, depending on its definition and pronunciation. Slough pronounced sluff can be a noun or a verb, while slough pronounced slou is a noun. The various definitions range from a multitude, to spinning on its axis, to skidding to a swamp, to a state of deep depression, to shedding one’s skin, or the skin to be shed.
Handing a writer a language that includes such words is akin to handing a painter a tray of oils that may or may not contain nitroglycerin. You, the writer, are never sure something won’t blow up in your face.