Where does “stí” come from?

stí (Old Norse) comes from Proto-Germanic stiją, from Proto-Indo-European steyh₂-, from Proto-Indo-European steh₂- — to stand.

Ancestry of “stí”, step by step

StepLanguageWordMeaning
1Proto-Germanicstiją—
2Proto-Indo-Europeansteyh₂-to stiffen
3Proto-Indo-Europeansteh₂-to stand
Every word from Proto-Indo-European steh₂- →Every word from Proto-Indo-European steyh₂- →Every word from Proto-Germanic stiją →