Where does “月曜日” come from?

月曜日 (Japanese) comes from Japanese 日, from Old Japanese 日, from Proto-Japonic *pi — day, sun.

月曜日 (Japanese): Monday

Definitions

  1. Monday

Ancestry of “月曜日”, step by step

月曜日 traces back through two separate lines of ancestry.

via Japanese 日

StepLanguageWordMeaning
1Japanese日Sunday
2Old Japanese日the sun; sunlight, sunshine; daytime, daylight
3Proto-Japonic*piday, sun

via Japanese 月曜

StepLanguageWordMeaning
1Japanese月曜the moon; Monday
Every word from Proto-Japonic *pi →Every word from Old Japanese 日 →Every word from Japanese 日 →