Welsh iach

← Breton yac'h (cognate)

← Gaulish Iaccus (cognate)

← Cornish yagh (cognate)

← Old Irish ícc (cognate)

← Middle Welsh yach (inherited)

→ Welsh iechyd (affix)

→ Welsh iachus (affix)

→ Welsh afiach (affix)

→ Old Irish ícc (cognate)