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我吃了半个苹果。
I ate half an apple.
One of two equal parts; fifty percent
这条路走了一半了。
We've walked half the way.
半小时后见。
See you in half an hour.
Used before nouns to indicate 'half of' (e.g., 半天 'half a day').
Middle; halfway; partially
他已经半醉了。
He's already half drunk.
这件事还没做完,只做了一半。
This isn't finished yet; only half is done.
Often paired with verbs to indicate incompleteness (e.g., 半信半疑 'half-believing, half-doubting').
Odd number (of a time unit, e.g., month, hour)
现在是三点半。
It's half past three.
Used in time expressions like '半点' (half past the hour).
In time phrases, '半' follows the hour (e.g., '三点半' = 3:30). For minutes, use '分' (e.g., '三点十五分' = 3:15).
'半' precedes the noun it modifies (e.g., '半杯水' 'half a glass of water'). It cannot stand alone as a subject/object.
From Old Chinese *pans (半), related to splitting or dividing equally. The character depicts a knife (刀) cutting an object in two.
When used as an adverb (e.g., '半死'), it intensifies the adjective (e.g., 'half-dead'). In compounds, it often implies 'incomplete' or 'partial' (e.g., '半生不熟' 'half-cooked').