Where does “ser” come from?

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

Ancestry of “ser”, step by step

StepLanguageWordMeaning
1Latinsūmto be, exist
2Proto-Italicezomto be
3Proto-Indo-Europeanh₁ésmifirst-person singular present indicative of...
4Proto-Indo-Europeanh₁ēs-to be

Words derived from “ser”

Every word from Proto-Indo-European h₁ēs- →Every word from Proto-Indo-European h₁ésmi →Every word from Proto-Italic ezom →