castes

/K AE1 S T S/
noun
  1. 1

    Any of the hereditary social classes and subclasses of South Asian societies.

  2. 2

    A separate and fixed order or class of persons in society who chiefly associate with each other.

  3. 3

    A class of polymorphous eusocial insects of a particular size and function within a colony.

Source: https://en.wiktionary.org/wiki/caste, https://en.wiktionary.org/wiki/castes