What is the meaning of Rishi?

A Vedic poet and seer who composed Rigvedic hymns, who alone or with others invokes the deities with poetry of a sacred character.

(post-Vedic) A Hindu sage or saint occupying the same position in India's history as the patriarchs of other countries, constituting a peculiar class of beings in the early mythical system, as distinct from Asuras, Devas and mortal men.