It is said that in the Zhou Dynasty and before, the emperors' tombs were also called "tombs", and they were not so expensive to build. Of course, they are much more luxurious and exquisite than ordinary people, but they are not as luxurious as the mausoleum behind them. At that time, the tomb after death was not so important in everyone's mind, so I wouldn't spend too much thought on it. Therefore, after the death of the king of the Zhou Dynasty, the burial place became a "tomb" instead of a "mausoleum".
It was not until around the Warring States period that Zhao called the emperor's burial place "Ling". In fact, Ling refers to a huge heaped-up mountain. The reason why it was called "Ling" was to highlight the emperor's supreme position and show that imperial power was the highest right at that time and could not be violated by anyone. Therefore, there are many things to be done in the construction of "Ling", such as height and layout, and "Ling" also has a unique meaning.
The emperor's mausoleum is called "Mausoleum", but what are people's names? In order to highlight the nobility of the emperor, the graves of the people can only be called "graves", and there are specific requirements for the construction scale. It is illegal to exceed the requirements and should be punished accordingly. Therefore, the emperor's mausoleum is called "Mausoleum" only to emphasize the supreme rights and status of the ruler.