Overview
In Indian religions, a rishi is an accomplished and enlightened person. They find mentions in various Vedic texts. Rishis are believed to have composed hymns of the Vedas. The Post-Vedic tradition of Hinduism regards the rishis as "great yogis" or "sages" who after intense meditation (tapas) realized the supreme truth and eternal knowledge, which they composed into hymns. The term appears in Pali literature as Ishi and in Buddhism, they can be either Buddhas, Paccekabuddhas, Arahats or a monk of high rank.
Etymology
According to Indian tradition, the word may be derived from two different meanings of the root 'rsh'. Sanskrit grammarians derive this word from the second meaning: "to go, to move". V. S. Apte gives this particular meaning and derivation, and Monier-Williams also gives the same, with some qualification.
Another form of this root means "to flow, to move near by flowing". (All the meanings and derivations cited above are based upon Sanskrit English Dictionary of Monier-Williams). Monier-Williams also quotes Tārānātha who compiled the great (Sanskrit-to-Sanskrit) dictionary named "ṛṣati jñānena saṃsāra-pāram" (i.e., "one who reaches beyond this mundane world by means of spiritual knowledge").
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