Where does “Sundai” come from?
Sundai (Saterland Frisian) comes from Old Frisian sunnandei, from Proto-Germanic *Sunnōn dag, from Latin dies Solis, from Latin sōl, from Proto-Indo-European sóh₂wl̥ — sun.
Sundai (Saterland Frisian): Sunday
Ancestry of “Sundai”, step by step