Where does “Mawuyọn” come from?

Mawuyọn (Gun) comes from Cornish -yon, from Proto-Celtic -onā.

Ancestry of “Mawuyọn”, step by step

Step	Language	Word	Meaning
1	Cornish	-yon	Noun pluralization suffix; causes vocalic ablaut...
2	Proto-Celtic	-onā	—