Origin

This character combines two ideas to express something happening with speed. The left component 疒 is a radical that relates to sickness or ailments—things that strike quickly and suddenly. The right component 矢 means arrow, which is the classic symbol for something moving at high speed. Together, they paint a picture of something as fast and sudden as an arrow or a sudden illness, which led to the meaning of "rapidly" or "quickly." The shape captures the sense of swift, urgent motion.