I would routinely use that "forbidden vocabulary" during class and in my exams whenever the opportunity is presented. After the grades come out, assuming my grade is lower than A+, I'd report the teacher for unfairly lowering my grade (whether that was obvious or not). I'd put the teacher on the spot!!
Teachers can't threaten to lower a grade for something this stupid and not be reported and scrutinized. I'd file a formal complaint with examples of when I used the terms in question. It would be VERY difficult for the teacher to support the grade I got as long as there were subjective areas included in the grading criteria.
If there are any essay questions on the exams or writing assignments, that grading contains lots of room for subjective evaluation and grading. Also group participation and anything else that is up to the teacher's arbitrary grades.
I'd call into question the validity of, and motives behind, the rules, and then ask for an automatic grade increase since there would be no way for the teacher to split hairs over why my grade was given.
