Looking up...
The natural satellite of the Earth, visible by reflected sunlight.
月亮升起了。
The moon has risen.
In Chinese, '月' can refer to both the moon itself and the lunar month.
A period of time corresponding to one lunar month (approx. 29.5 days).
这个项目需要三个月完成。
This project will take three months to complete.
Often used in contexts like pregnancy (e.g., '三个月' = three months pregnant).
A monthly period or menstruation.
她这个月来例假了。
She got her period this month.
Colloquially referred to as '大姨妈' (dà yí mā) in modern slang.
'月亮' specifically refers to the moon as a celestial body, while '月' can also mean 'month' or appear in compounds (e.g., '月份'). For example, '一个月' means 'one month,' not 'one moon.'
In time expressions, '月' is often paired with a number or ordinal (e.g., '一月' for January, '上个月' for last month). It is rarely used alone to mean 'month' in modern speech.
The character '月' originates from the pictogram of a crescent moon in oracle bone script (甲骨文), evolving into its current form. It was originally a depiction of the moon's phases and later extended to mean 'month' due to the lunar calendar's prevalence in ancient Chinese culture.
'月' is a bound morpheme in many compounds (e.g., '月份' for month, '月光' for moonlight). It is also used in time expressions like '月曜日' (Monday, in Japanese) and '月曜日' (same, in Korean). In modern Chinese, '月' alone typically refers to the moon when used as a noun.