Where does “èstre” come from?

èstre (Occitan) comes from Old Occitan esser, from Latin sūm, from Proto-Italic ezom, from Proto-Indo-European h₁ésmi, from Proto-Indo-European h₁ēs- — to be.

Ancestry of “èstre”, step by step

StepLanguageWordMeaning
1Old Occitanesserto be
2Latinsūmto be, exist
3Proto-Italicezomto be
4Proto-Indo-Europeanh₁ésmifirst-person singular present indicative of...
5Proto-Indo-Europeanh₁ēs-to be
Every word from Proto-Indo-European h₁ēs- →Every word from Proto-Indo-European h₁ésmi →Every word from Proto-Italic ezom →