Type Word Usage Old Celtic (Hypothetical) Meaning & History Celtic word meaning "king" [1]. Related ItemsFamily Tree·Details Other Languages & Culturesrí, rígain(Old Irish) ri(Old Welsh) Given Name DescendantsToutorīxs(Brythonic) Dumnorix(Gaulish) Ríona, Ríonach(Irish) Ríghnach, Ríoghnach(Irish Mythology) Tudur(Medieval Welsh) Tudor, Tudur(Welsh) Sources & References Matasović, Ranko. Etymological Dictionary of Proto-Celtic. Brill, 2009, page 311.