A makeup (test/exam) is a test taken in school because you were not able to take a previous test. But, I wondered how you call an exam that you take again because you failed it the first time.
My American colleague told me that it should be called a "retake." He also said, though, "it's very rare." In Japan, it's not uncommon. I have taken a retake a couple of times. And one of my Japanese colleagues said she had taken many times.
I think that this difference comes from that of term exams between Japan and the states. In Japan, sometimes the mean score of a term exam is around 50 percent. And 75 percent is a very good score at times. However, as you know, 75 percent is C in the states.