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Definition: case study

1. a process or record of research in which detailed consideration is given to the development of a particular person, group, or situation over a period of time. "the case study was undertaken over a period of two months through a series of visits to the school"
2. a particular instance of something used or analyzed in order to illustrate a thesis or principle. "airline deregulation provides a case study of the effects of the internal market"

Source: Oxford languages

These are cases where I've done a significant amount of original research.