Where does “به” come from?

به (Ottoman Turkish) comes from Byzantine Greek μρε, from Ancient Greek μωρέ, from Ancient Greek μωρός, from Proto-Indo-European muHrós — dull, stupid.

Ancestry of “به”, step by step

Step	Language	Word	Meaning
1	Byzantine Greek	μρε	—
2	Ancient Greek	μωρέ	—
3	Ancient Greek	μωρός	slow, sluggish; slow, dull, foolish, stupid;...
4	Proto-Indo-European	muHrós	dull, stupid

Words derived from “به”

be
бе
бе
ب
abece
aga be

Every word from Proto-Indo-European muHrós →Every word from Ancient Greek μωρός →Every word from Ancient Greek μωρέ →