The Proto-Turkic word *örs(en)
Word *örs(en)
Meaning river, river bed, to flow
Synonyms *iak-

Comments
S. A. Starostin, A. V. Dybo, O. A. Mudrak - An Etymological Dictionary of Altaic Languages, 2003, Brill

Other words that might be of interest
*bū(n)ŕ < būĺ(V)-ŕ ‘ice’, *doŋ ‘cold, frost, frozen, to freeze, be frozen’, *jag- ‘rain, to rain’, *čɨj(ɨk) ‘wet, soaking, moist, dew, moisture’, *sɨb ‘water’, *dal-g- ‘wave’, *kōm ‘wave’, yul ‘stream, brook, fountain’, *batɨ-g ‘swamp, marsh’