Origin

This character most likely combines the idea of a knife or blade (the left component, which derives from the radical for cutting tools) with a sound component on the right that suggests the pronunciation "suat" or similar. Over time, the character came to mean "printing" and "brushing" because both actions involve repeatedly scraping or pressing a tool — whether a printing block or a brush — across a surface in a controlled way. The connection to printing is especially strong in Chinese and Japanese, where woodblock printing uses a scraping motion similar to brushing.