源泉

HSK 7-9

yuánquán

source; origin (often abstract)

well-spring; water source; fig. origin

源泉是水的来源。

yuánquán shì shuǐ de láiyuán.

The source is where water comes from.

这个理论的源泉来自于古代哲学。

zhège lǐlùn de yuánquán láizì yú gǔdài zhuānyè.

The origin of this theory lies in ancient philosophy.