Where does “мьгновениѥ” come from?

мьгновениѥ (Old Church Slavonic) comes from Proto-Slavic *mьgnovenьje, from Proto-Slavic *mьgnǫti, from Proto-Slavic migati, from Proto-Balto-Slavic meyg-, from Proto-Indo-European meygʰ-.

Ancestry of “мьгновениѥ”, step by step

StepLanguageWordMeaning
1Proto-Slavic*mьgnovenьjemoment, instant, twinkling
2Proto-Slavic*mьgnǫti—
3Proto-Slavicmigatito blink
4Proto-Balto-Slavicmeyg-—
5Proto-Indo-Europeanmeygʰ-—
Every word from Proto-Indo-European meygʰ- →Every word from Proto-Balto-Slavic meyg- →Every word from Proto-Slavic migati →