In mathematics, a conglomerate is a collection of classes, just as a class is a collection of sets. A quasi-category is like a category except that its objects and morphisms form conglomerates instead of classes. The subclasses of any class, and in particular, the collection of all classes (every class is a subclass of the class of all sets), form a conglomerate.
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Conglomerate (set theory) Wikipedia(Text) CC BY-SA