Where does “yez” come from?

yez (Middle Breton) comes from Proto-Brythonic jeiθ, from Proto-Celtic yextis, from Proto-Indo-European yek- — to utter.

Ancestry of “yez”, step by step

StepLanguageWordMeaning
1Proto-Brythonicjeiθlanguage
2Proto-Celticyextislanguage, speech
3Proto-Indo-Europeanyek-to utter

Words derived from “yez”

Every word from Proto-Indo-European yek- →Every word from Proto-Celtic yextis →Every word from Proto-Brythonic jeiθ →
yez — Etymology, Origin & Word History | Etymology Explorer