Where does “ἐσύ” come from?

ἐσύ (Byzantine Greek) comes from Ancient Greek σύ, from Proto-Hellenic tú, from Proto-Indo-European túh₂ — you, thou.

Ancestry of “ἐσύ”, step by step

StepLanguageWordMeaning
1Ancient Greekσύsecond person singular personal pronoun: you
2Proto-Hellenictúyou, thou
3Proto-Indo-Europeantúh₂you, thou

Words derived from “ἐσύ”

Every word from Proto-Indo-European túh₂ →Every word from Proto-Hellenic tú →Every word from Ancient Greek σύ →