[bǐ yù]
（譬喻； 一种修辞方式） metaphor or simile; analogy; figure of speech; allegory
This is just a figure of speech
这只是一个比喻说法。
The atomic structure is often compared to a miniature solar system.
原子结构时常被比喻为微型太阳系。
We often compare the flow of electrical charges to the flow of water.
我们时常把电荷的流动比喻为水的流动。