Entry from British & World English dictionary
noun (plural Adivasis)
1A member of any of the aboriginal tribal peoples living in India before the arrival of the Aryans in the second millennium bc. 1.1A descendant of any of the Adivasi peoples.
from modern Sanskrit ādivāsī, from Sanskrit ādi 'earliest' + vāsi 'inhabitant'.
Definition of Adivasi in: