Eight Legions

Etymology

The name aṣṭasenā (अष्टसेना) is composed of two Sanskrit terms.

Aṣṭa (अष्ट) means eight, with connections to the Latin octo and the Persian hašt (هشت). Senā (सेना) means legion, but can be rendered army, general, warrior and the like. Yet for the sake of accuracy contrary to the custom, each legion has a unique standard/banner and is composed just of several thousand foot soldiers. For that size of a military unit there is a fitting Sanskrit term "Dhvajinī", i.e. "body of troops bearing a standard". "Sena" is better to translate as "army" due to the fact that enormous Kuru and Pāṇḍava troops that gathered on the battlefield were called "kurupāṇḍava-sena" (one can't label two huge military forces fighting each other as just one legion), and more than that, all wars in India are patronized by the god of war Kārtikeya who probably plays both sides in any conflict if adversary combatants worship devas. His wife's name is Sena, a goddess, commonly known as Deva-Sena, the personified armament of the gods. There were plenty of legions in India serving various kings and lords, but all military forces as a whole could be figuratively named an army, i.e. "Sena" - the Shakti through which the god of war imposed his will.

Summary