An Etymological Dictionary of Astronomy and Astrophysics

All, universally.

Etymology (EN): L. omni-, combining form of omnis “all, every,” of unknown origin.

Etymology (PE): Visp-, from Mid.Pers. visp- “all;” O.Pers. visa-, vispa- “all;” Av. vīspa- “all, every, entire, universal” (vīspô.ayāra- “lasting all the days,” vīspô.vīδvah- “knowing everything, omniscient”); cf. Skt. vīśva- “all, every; whole, universal.”