秋分（しゅうぶん、shuubun）
- autumn equinox

The Japanese word 秋分, read as しゅうぶん, refers to the autumnal equinox. It is one of the 24 solar terms (二十四節気) in the traditional East Asian lunisolar calendars. The autumnal equinox marks the point in the year when the sun crosses the celestial equator from north to south. This results in roughly equal amounts of daylight and night. It usually falls around September 22nd or 23rd in the Gregorian calendar. 秋分 also represents the beginning of the fall season, as understood in Japan.

⚫︎秋分の日 Translation: The autumnal equinox day. ⚫︎秋分の日は祝日です。 Translation: The autumnal equinox day is a national holiday. ⚫︎今年の秋分は9月23日です。 Translation: This year's autumnal equinox is September 23rd.

秋分 is typically used in formal or informative contexts. It's common when discussing the calendar, seasons, or related events like the autumnal equinox holiday in Japan (秋分の日). You can use it to talk about the date of the equinox, the changes in weather, and the transition into autumn. It is appropriate to use in conversation, articles, and announcements.

秋分 is usually written in kanji 秋分. The reading in hiragana is しゅうぶん. There are no other common ways to write this word. There are no variations in the okurigana.

There are no direct synonyms, as 秋分 specifically refers to the autumnal equinox. However, phrases related to autumn or the season's transition could be considered related.

There are no direct antonyms for 秋分 because it's a specific astronomical event. The spring equinox, 春分 (しゅんぶん), could be considered an opposite event.

秋分の頃になると、日中の時間が短くなります。 ・Translation: Around the time of the autumnal equinox, the length of daylight decreases. ・Explanation: This sentence describes the typical change in daylight hours around the time of the autumnal equinox.

秋分の日は、お墓参りに行く人も多いです。 ・Translation: On the day of the autumnal equinox, many people go to visit graves. ・Explanation: This sentence refers to a common custom in Japan, where families visit and clean ancestral graves on this holiday.

The word 秋分 is composed of two kanji: 秋 (あき - autumn) and 分 (ぶん - division, minute). The term reflects the division of the year into seasons and describes the point when autumn begins. It originates from Chinese astronomical practices, where the solar terms were established to track the sun's position.