Where does “-fua” come from?

-fua (Swahili) comes from Old Irish fo, from Proto-Celtic uɸo, from Proto-Indo-European upó, from Proto-Indo-European h₃ewp-.

Ancestry of “-fua”, step by step

StepLanguageWordMeaning
1Old Irishfounder, beneath; towards; through, throughout
2Proto-Celticuɸounder, below
3Proto-Indo-Europeanupóunder, below
4Proto-Indo-Europeanh₃ewp-—

Words derived from “-fua”

Every word from Proto-Indo-European h₃ewp- →Every word from Proto-Indo-European upó →Every word from Proto-Celtic uɸo →