Where does “alba” come from?

Alba comes from Latin alba, the feminine form of albus meaning "white," ultimately from Proto-Indo-European h₂élbʰos with the same sense.

alba (English): A type of lyrical poetry, traditionally...

Definitions

Step	Language	Word	Meaning
1	Occitan	alba	—
2	Latin	Albus	—
3	Proto-Italic	alβos	white
4	Proto-Indo-European	h₂élbʰos	white

alba — Etymology, Origin & Word History | Etymology Explorer