Where does “Бет” come from?

Бет (Bulgarian) comes from English Beth, from Proto-Semitic bayt- — house.

Ancestry of “Бет”, step by step

StepLanguageWordMeaning
1EnglishBethThe second letter of the Phoenician alphabet, 𐤁
2Proto-Semiticbayt-house
Every word from Proto-Semitic bayt-Every word from English Beth