Where does “一昨日” come from?

一昨日 (Japanese) comes from Japanese 日, from Old Japanese 日, from Proto-Japonic *pi — day, sun.

一昨日 (Japanese): the day before yesterday, two days ago

Definitions

  1. the day before yesterday, two days ago

Ancestry of “一昨日”, step by step

一昨日 traces back through 3 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 遠

StepLanguageWordMeaning
1Japanese遠distant, far-off; a distant place; a time far...
2Middle Chinese遠—

via Old Japanese つ

StepLanguageWordMeaning
1Old Japaneseつ—

Words derived from “一昨日”

Every word from Proto-Japonic *pi →Every word from Old Japanese 日 →Every word from Japanese 日 →