清む
すむ · sumu · JLPT N3 · verb-godan
to clear
💧 清 = 氵 water + 青 blue: water clear enough to show blue
The kanji 清 joins the water radical 氵 with 青 (blue, also the sound component), so its core sense is clean, clear water. 清む (sumu) is when water, air or sky turns clear. It sounds the same as 住む (to live) and 済む (to finish), so the kanji tells you which one you have.
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.