Type Word Usage Old Welsh Meaning & History Old Welsh word meaning "king" [1]. Related ItemsDetails Other Languages & Culturesrīxs(Old Celtic) rí, rígain(Old Irish) Given Name DescendantsRiderch, Rotri(Old Welsh) Rhodri, Rhydderch, Roderick(Welsh) Surname DescendantRhydderch(Welsh) Same Spellingri 2, ri 3, ri 4, ri 5, ri 6, ri 7, ri 8, rí, rì Sources & References Matasović, Ranko. Etymological Dictionary of Proto-Celtic. Brill, 2009, page 311.