I’m annotating the passage in DN 27 where it gives origins of the caste names.
I know that there has been considerable scholarly work on these, and I’m wondering if anyone is familiar with it, or can refer me to it? I’m especially interested in PIE origins.
So far I had:
“Aristocrat” (khattiya; Sanskrit kṣatriya) is related to khatta (“authority”, “power”) hence “ruling class”. The sutta, however, relates it to khetta, “field”. The two senses possibly stem from the same root kṣi in the sense “owner”, “master” with the “field” being the dominion owned by the chief. In Pali suttas, the primary connotation of the khattiya was of an aristocratic land-owning class, so the connection with “field” is apt. Khattiyas are often said to be a “warrior” caste, but that is not a primary association in the suttas. They only rarely are depicted as having anything to do with the military, which had already become professionalized by the time of the Buddha.
Modern linguists trace the Proto-Indo-European root of rāja as *reg in the sense “[one who leads people in a] straight line”, literally “ruler” or “regulator”. The pun here is meant to emphasize the obligations that a ruler has for their people. As here, rājā and khattiya can have the same meaning, although commonly a rājā is an actual king or chief, while khattiya is the class from which the rulers come.
√Bāh roughly evokes brāhmaṇa. Such puns which don’t quite land are sometimes used to infer a language underlying Pali. Brāhmaṇa is a Sanskrit form, and the colloquial pronunciation may have been closer to bāhmaṇa.