清
qīng · HSK 6
clean
💧 氵water + 青 blue-green: water so clear it looks blue
青 (qīng) means blue-green and also gives the pronunciation. The water radical 氵narrows the sense to liquid purity. Same logic: if nothing taints it, water runs clear and cool.
清 — water 氵 + 青 (azure/blue-green, phonetic)
清 is a semantic-phonetic compound. The water radical 氵 gives the meaning—originally clear, unmuddied water—while 青 (qīng, azure) supplies the sound and reinforces the image of pure blue-green water. The sense later broadened from 'clear water' to 'clear, pure, clean' in general.