Where does “霓虹金” come from?

霓虹金 (Chinese) comes from Japanese 日本人, from Japanese 日本, from Japanese 日, from Old Japanese 日, from Proto-Japonic *pi — day, sun.

霓虹金 (Chinese): Japanese person

Definitions

Step	Language	Word	Meaning
1	Japanese	日本人	a Japanese person, Japanese people
2	Japanese	日本	{{l\|en\|Japan}}; Japan
3	Japanese	日	Sunday
4	Old Japanese	日	the sun; sunlight, sunshine; daytime, daylight
5	Proto-Japonic	*pi	day, sun