end of autumn; late autumn
Obsolete term. Refers to the final part of autumn, roughly corresponding to late October and November in the modern calendar.
ninth month of the lunar calendar
Refers specifically to the ninth month of the traditional Japanese lunar calendar, which roughly corresponds to October in the modern calendar. Used in historical or poetic contexts.
In this late autumn season, I hope you are doing well.
The ninth month of the old lunar calendar corresponds to modern October.
Sino-Japanese compound from 季 (season) and 秋 (autumn). The historical derivation is straightforward, but the term itself is now obsolete.