Where does “Ruaidrí” come from?

Ruaidrí (Old Irish) comes from Old Irish rí, from Proto-Celtic rīxs, from Proto-Indo-European h₃rḗǵs, from Proto-Indo-European h₃reǵ- — to straighten, to right oneself; right; just.

Ancestry of “Ruaidrí”, step by step

Ruaidrí traces back through two separate lines of ancestry.

via Old Irish rí

StepLanguageWordMeaning
1Old Irishríking
2Proto-Celticrīxsking
3Proto-Indo-Europeanh₃rḗǵsking, ruler
4Proto-Indo-Europeanh₃reǵ-to straighten, to right oneself; right; just

via Old Irish rúad

StepLanguageWordMeaning
1Old Irishrúadred, reddish
2Proto-Celticroudosred
3Proto-Indo-Europeanh₁rewdʰ-red

Words derived from “Ruaidrí”

Every word from Proto-Indo-European h₃reǵ- →Every word from Proto-Indo-European h₃rḗǵs →Every word from Proto-Celtic rīxs →
Ruaidrí — Etymology, Origin & Word History | Etymology Explorer