Where does “faia” come from?

faia (Old Portuguese) comes from Latin fagea, from Latin fāgus, from Proto-Italic fāgos, from Proto-Indo-European bʰeh₂ǵos — beech.

Ancestry of “faia”, step by step

Step	Language	Word	Meaning
1	Latin	fagea	beech
2	Latin	fāgus	—
3	Proto-Italic	fāgos	—
4	Proto-Indo-European	bʰeh₂ǵos	beech

faia — Etymology, Origin & Word History | Etymology Explorer