autumn when the moon is beautiful
Poetic phrase evoking the beauty of the moon in autumn; often used in classical or literary contexts.
月の秋には、名月を愛でる宴が開かれる。
In the autumn when the moon is beautiful, banquets are held to admire the harvest moon.
Compound of 月 (moon) + の (possessive particle) + 秋 (autumn). The exact origin is uncertain; it is a poetic expression found in classical Japanese literature.