淀粉
diàn fěn · HSK 7
starch
🥔 diàn fěn = settle + powder — the powder that settles out of water
When you wash starchy foods like potatoes, the starch sinks and settles (淀 diàn = sediment) as a fine powder (粉 fěn = powder). Starch is literally the sediment-powder.
粉 — rice 米 + divide 分
A semantic-phonetic compound: 米 (rice/grain) gives the meaning, while 分 (fēn, 'divide') hints at the sound. It originally referred to rice flour or finely ground powder, then extended to any powder and to the pale pinkish color of such powders.