- a primary division of a class.
- a subordinate class, especially one of persons who lack the rights and privileges of the primary class: a subclass of migrant workers.
- a category of related orders within a class.
- to place in a subclass.
- a principal subdivision of a class
- a taxonomic group that is a subdivision of a class
- maths another name for subset (def. 1)
- to assign to a subclass
