Where does “sé” come from?

sé (Middle Irish) comes from Old Irish é, from Proto-Indo-European éy, from Proto-Indo-European h₁e-.

Ancestry of “sé”, step by step

StepLanguageWordMeaning
1Old Irishéhe; it; they
2Proto-Indo-Europeanéythe; demonstrative pronoun; this one, he
3Proto-Indo-Europeanh₁e-—

Words derived from “sé”

Every word from Proto-Indo-European h₁e- →Every word from Proto-Indo-European éy →Every word from Old Irish é →