Where does “vastō” come from?

vastō (Latin) comes from Latin vastus, from Proto-Celtic wāstos, from Proto-Indo-European h₁weh₂- — to leave, abandon, give out.

Ancestry of “vastō”, step by step

Step	Language	Word	Meaning
1	Latin	vastus	Empty, unoccupied, i.e. waste, desert; Desolate,...
2	Proto-Celtic	wāstos	empty
3	Proto-Indo-European	h₁weh₂-	to leave, abandon, give out

vastō — Etymology, Origin & Word History | Etymology Explorer