まんげつ満月mangetsu
1.
A celestial event where the moon is completely illuminated, appearing as a perfect circle in the night sky, typically occurring when it is positioned directly opposite the sun in relation to the Earth.
2.
The specific night when the moon is at its fullest brightness, often associated with seasonal celebrations in October of the lunar calendar.
3.
A term used in traditional Japanese music to describe a specific part of the biwa, drawing a metaphorical connection to the fullness and brightness of the moon.
Example:
満月でしたか新月でしたか。