I’ve written about the all-too-common mistake of substituting a homonym for the intended word. (And if “homonym” isn’t triggering enough brain cells, it refers to those words that sound alike, but are spelled differently.)
Now, I don’t consider using the wrong version of a homonym a mortal sin – except when it’s done by someone in the media. Professionals should know better. During coverage of the recent flooding near my home, I saw several examples of writers and reporters referring to a barrier that holds back water as a “levy.” (At least they didn’t misidentify a dike as a “dyke.” We won’t even go there.)