Where does “Nippon” come from?

Nippon is the English exonym for Japan, derived from Japanese にっぽん, whose ultimate origin and meaning remain uncertain.

Ancestry of “Nippon”, step by step

Step	Language	Word	Meaning
1	Japanese	日本	{{l\|en\|Japan}}; Japan
2	Japanese	日	Short for 日曜日 : Sunday; the sun; sunlight,...
3	Old Japanese	日	the sun; sunlight, sunshine; daytime, daylight
4	Proto-Japonic	*pi	—

Nippon — Etymology, Origin & Word History | Etymology Explorer