When I was in college taking English 101, I used a perfectly cromulent word in one of my papers. The teacher had this dinky little book, smaller than an ordinary paperback, which I don’t think was even a dictionary, just a list of hard words or something similar. Of course, the word I used was not in that dinky book, so he claimed it wasn’t a word and wanted me to change it. We had a bit of argument about it and he wanted me to redo the paper with the word changed. I redid the paper (other changes), but didn’t change the word, so we had another argument. I could have shown him the word in my much larger dictionary, but didn’t think to bring it with me to his office. Actually, I had a hard time believing he was unfamiliar with the word. The word, by the way, was “tout” used as a verb. I don’t recall if I got marked down for using it or not.
That would be pretty nasty treatment if it happened.
Why would you punish a student who’s so enamored of language that he trolls through dictionaries looking for cool new words for being unlucky in his discovery?