Where does “trueiniaid” come from?

trueiniaid (Welsh) comes from Welsh -iaid, from Welsh -iad, from Proto-Brythonic -ad, from Proto-Brythonic -atus, from Proto-Brythonic -ātus.

Ancestry of “trueiniaid”, step by step

StepLanguageWordMeaning
1Welsh-iaid-s; plural of -iad
2Welsh-iadshow the action of a verb or its result; suffix...
3Proto-Brythonic-ad—
4Proto-Brythonic-atus—
5Proto-Brythonic-ātus—
Every word from Proto-Brythonic -ātus →Every word from Welsh -iad →Every word from Welsh -iaid →