midnight; the hour of the Rat
Traditional Japanese timekeeping: the two-hour period centered on midnight (roughly 11 p.m. to 1 a.m.), associated with the Rat in the Chinese zodiac.
In old Japan, the hour of the Rat referred to the period from 11 p.m. to 1 a.m.
From the Chinese zodiac system adopted in Japan, where the day was divided into twelve two-hour periods each named after an animal. 子 (ne) is the Rat, the first sign, and its period corresponds to midnight.