Rishi
In the Vedas the term Rishi also known as Rushi (Sanskrit: ऋषि ṛṣi) denotes an inspired poet of Vedic hymns. Post-Vedic tradition of Hinduism regards the Rishis (or Phra Ruesi (Lao: ພະລືສີ, Thai: พระฤาษี) in Laos and Thailand) as "seers" or "sages", who after intense meditation (Tapas) realized truths and eternal knowledge, which they composed into hymns.
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").
More than a century ago, Monier-Williams tentatively suggested a derivation from drś "to see". Monier-Wiliams also quotes the Hibernian (Irish) form arsan (a sage, a man old in wisdom) and arrach (old, ancient, aged) as related to rishi. Monier-Williams also conjectures that the root drish (to see) might have given rise to an obsolete root rish meaning "to see".
However, the root has a close Avestan cognate ərəšiš "an ecstatic" (see also Yurodivy, Vates). Yet the Indo-European dictionary of Julius Pokorny connects the word to a PIE root *h3er-s meaning "rise, protrude", in the sense of "excellent" and thus cognate with Ṛta and and Asha. In Sanskrit, forms of the root rish become arsh- in many words, (e.g., arsh)
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