Where does “小の月” come from?

小の月 (Japanese) comes from Japanese しょう, from Middle Chinese 城.

小の月 (Japanese): month with 30 days or less

Definitions

  1. month with 30 days or less

Ancestry of “小の月”, step by step

小の月 traces back through two separate lines of ancestry.

via Japanese しょう

StepLanguageWordMeaning
1Japaneseしょう正 proper; straight, direct; genuine, true; 兄鷹 a...
2Middle Chinese城—

via Japanese つき

StepLanguageWordMeaning
1Japaneseつき月 month, moon; 付き attached to, with, impression;...
Every word from Middle Chinese 城 →Every word from Japanese しょう →