I've decided to begin a running feature on things I discover in students' submitted work that annoy me or amuse me. Usually these will be pet peeves. Sometimes they will just be odd expressions or statements. I'll begin with one that I see very regularly, and it's not just in student papers but all over the internet. It's the expression "close-minded".
It amazes me how common this is, but it doesn't make sense. No one is saying that your mind is close to something, which is what "close-minded" suggests. Even if your mind is a material object (which it isn't), this isn't about having your mind physically close to anything. What people mean is that someone is closed-minded, i.e. their mind is closed. Somehow the 'd' has become elided in how we pronounce it, and people who don't read have spelled it the way they hear it. It has become so common a way of spelling the term that there are more Google searches for "close-minded" than there are for "closed-minded".
Dictionaries do unfortunately include both, and I'm not trying to say that this is incorrect. I think it's reached a point where I can't confidently say that. But it is nevertheless stupid and annoying that it's gotten to that point. The question is whether I can justify correcting it on students' paper.
Here's one suggestion. One of the things a college course involving academic writing should teach is how not to come across as ignorant or as a non-reader. If enough people will conclude that upon seeing someone write "close-minded", then it might be worth correcting for the sake of how viewers of the writing of the student in question will see it. But I think that argument might apply to things I don't think I should correct (e.g. the singular "they", which I eagerly encourage).