a small extra floor between one floor of a building and the next floor up

You can look down from the mezzanine onto the ground floor lobby. 你可以从夹楼往下看到一楼大堂。

The shoe department is on the mezzanine floor. 鞋品部在夹层楼面。

the front few rows of seats of the level above ground, or all of the level above ground, in a place such as a theatre or sports stadium