Where does “пяна” come from?

пяна (Bulgarian) comes from Proto-Slavic pěna, from Proto-Balto-Slavic *(s)páināˀ, from Proto-Indo-European (s)poH(y)-, from Proto-Indo-European speh₁- — to succeed, to prosper.

пяна (Bulgarian): foam, froth a mass of small bubbles formed on the surface of a liquid by boiling, fermentation, carbonization, agitation, etc

Definitions

  1. foam, froth a mass of small bubbles formed on the surface of a liquid by boiling, fermentation, carbonization, agitation, etc

Ancestry of “пяна”, step by step

StepLanguageWordMeaning
1Proto-Slavicpěnafoam
2Proto-Balto-Slavic*(s)páināˀ
3Proto-Indo-European(s)poH(y)-foam
4Proto-Indo-Europeanspeh₁-to succeed, to prosper
Every word from Proto-Indo-European speh₁-Every word from Proto-Indo-European (s)poH(y)-Every word from Proto-Balto-Slavic *(s)páināˀ