Origin

The character 弧 combines the bow radical on the left, which shows the actual object—a curved weapon or tool—with a phonetic component on the right that hints at how to pronounce it. The bow naturally curves when drawn, so it became the visual basis for expressing the concept of an arc or arch. The right component provides a sound hint for reading, not an additional meaning. Over time, this character extended beyond just bows to mean any curved line or arc in a more general sense.