a category / to categorize
A category is a separateย partย of a system, which has its own name. So, in the Oscars, there are a number of different categories for acting: Best actor, Best supporting actor etc. If youย divide something into different parts, you categorise (or โcategorizeโ) it.
Research is oftenย categorisedย as โqualitativeโ or โquantitativeโ but frequently it uses elements of each approach.ย