full moon; moon on the 15th day of the month (by the lunar calendar)
full moon of the eighth lunar month
貴族は望月を眺めた。
The noble gazed at the full moon.
望月の夜、観月祭が催された。
The moon-viewing festival was held on the night of the full moon.
望月が静かに昇り、里を淡く照らした。
The full moon slowly rose, softly illuminating the village.