1.
half moon
the moon when it appears as a semicircle, either first quarter or last quarter
今夜は半月だ。
Tonight there's a half moon.
半月が雲の間から見えた。
The half moon was visible between the clouds.
半月板を怪我した。
I injured my meniscus.
2.
half a month; two weeks
a period of approximately two weeks or 15 days
半月で十キロ痩せた。
I lost 10 kilograms in half a month.
旅行まで半月切った。
There's less than half a month until the trip.
引っ越し準備に半月かかった。
It took half a month to prepare for the move.
COMPOUND:
半 (half) + 月 (moon, month)
MOON PHASES:
- 新月 - new moon
- 三日月 - crescent moon
- 半月 - half moon
- 満月 - full moon
- 上弦の月 - first quarter moon
- 下弦の月 - last quarter moon
ANATOMY:
- 半月板 - meniscus (knee cartilage, named for its half-moon shape)
CONTRAST:
- 半月 (two weeks) vs 一ヶ月 (one month)