What is would be my "relationship" with a recommender whose class I was a TA for? I'm applying to graduate school. One of the people who are going to write a reference letter for me was my professor in a course. Also, I later became a TA in her class.
I have to determine my relationship with this recommender in a field that can take only a few words. What should I put there?
How about "student and later assistant"? I think it would be well understood. Make it teaching assistant if you want five words instead of four. 

Or if you want to turn it to reference them instead of yourself: "professor, later TA supervisor".