While the concept of a 60-minute hour is universal, the Chinese term 小时 (xiǎoshí) offers a glimpse into the logic of the language. Unlike the English word “hour,” which has opaque origins from Ancient Greek, 小时 (xiǎoshí) is transparently “small time.” This reflects a common feature in modern Chinese, where complex ideas are often built from simple, logical character components. In terms of cultural values, using 小时 (xiǎoshí) accurately is key to demonstrating punctuality and reliability, which are highly valued in Chinese business and formal settings. An appointment at `三点 (sān diǎn - 3 o'clock)` is expected to be on time. However, when describing a duration, it's common to add words like `左右 (zuǒyòu - around/approximately)`, showing a bit more flexibility. For instance, saying a journey takes `五个小时左右 (wǔ ge xiǎoshí zuǒyòu)` means “around five hours,” which is a very common and natural way of speaking.
小时 (xiǎoshí) is a universally used term in all contexts, from formal written documents to casual everyday conversation. It is the default, neutral word for “hour.”
This is the primary function of 小时. It answers the question “how long?”.
In spoken Chinese, especially in northern regions, you will frequently hear 钟头 (zhōngtóu) used interchangeably with 小时. They mean the same thing, but 小时 is slightly more formal and is the standard for writing, while 钟头 is purely colloquial.