Where does “былы” come from?

былы (Belarusian) comes from Belarusian быць, from Old East Slavic бꙑти, from Proto-Slavic *byti, from Proto-Balto-Slavic bū́ˀtei, from Proto-Indo-European bʰuH- — to become, grow, appear.

былы (Belarusian): former, previous, erstwhile, ex

Definitions

  1. former, previous, erstwhile, ex

Ancestry of “былы”, step by step

StepLanguageWordMeaning
1Belarusianбыцьto be
2Old East Slavicбꙑтиto be
3Proto-Slavic*byti—
4Proto-Balto-Slavicbū́ˀteito be
5Proto-Indo-EuropeanbʰuH-to become, grow, appear
Every word from Proto-Indo-European bʰuH- →Every word from Proto-Balto-Slavic bū́ˀtei →Every word from Proto-Slavic *byti →