Where does “*špa” come from?

*špa (Proto-Pathan) comes from Proto-Iranian xšáfš, from Proto-Indo-Iranian kšáps, from Proto-Indo-European kʷséps — night.

Ancestry of “*špa”, step by step

StepLanguageWordMeaning
1Proto-Iranianxšáfšnight
2Proto-Indo-Iraniankšápsnight
3Proto-Indo-Europeankʷsépsnight

Words derived from “*špa”

Every word from Proto-Indo-European kʷséps →Every word from Proto-Indo-Iranian kšáps →Every word from Proto-Iranian xšáfš →