Parivrajaka refers to wandering ascetics or renunciants who have left their homes and societal ties. Upasaka refers to a lay follower of Buddhism or other Shramana traditions who is not a monk or nun but observes basic precepts. Shramana refers to ascetics and renunciants generally, particularly those who rejected the authority of the Vedas and the Brahmanical system, such as Buddhists, Jains, and Ajivikas. They represent a tradition distinct from the Brahmanical priesthood and are not typically associated with high status within that system.