下弦(かげん)

かげん
noun
last quarter moon; waning half-moon
naturescience
1. last quarter moon; waning half-moon; third quarter
The phase of the moon approximately one week after the full moon, when the left half of the moon is illuminated (as seen from the Northern Hemisphere).
今夜(こんや)は下弦(かげん)の月(つき)だ。
Tonight is a last quarter moon.
The last quarter moon rises at midnight.
After the full moon, it passes through the last quarter and eventually becomes a new moon.

One of the four principal lunar phases. The word literally means 'lower bowstring,' referring to the shape of the half-moon resembling the lower half of a drawn bow.

Related words

Common collocations

Etymology

弦(げん) means 'bowstring.' One explanation is that the half-moon sets with its flat edge facing downward, like a bow's lower string; another ties 上(じょう) and 下(か) to the first and second halves of the lunar month. The opposite is 上弦(じょうげん) (upper bowstring).