扩散
kuò sàn · HSK 7
to spread
💨 扩 expand + 散 scatter = expand and scatter outward = to spread, diffuse
扩 means to expand or enlarge; 散 means to scatter or disperse. Together they mean something widening as it scatters, like smoke or news spreading.
扩 — hand radical 扌 + 广 (kuàng/guǎng, wide)
扩 is the simplified form of 擴. It is a semantic-phonetic compound: the hand radical 扌 suggests the action of pushing or stretching, while 广 hints at the sound and the idea of wideness. Together they convey 'to extend' or 'to expand'.
散 — 月 (meat) + 攵 (action) + 卄 (hemp fibers)
Originally depicted beating hemp fibers apart with a stick, with 月 (meat/flesh) added later. The core image of separating or scattering things gave rise to meanings like 'scatter,' 'disperse,' and 'loose/leisurely.' The 攵 component signals an action done by hand.