清ます
すます · sumasu · JLPT N1 · verb-godan
to clear; to make clear; to listen for
💧 清 = clear (清水 = clear water) + causative す = make it clear, or listen out
The kanji 清 means clear, as in 清水 (clear water). The causative ending turns it into the act of making something clear, or listening closely until the sound comes through.
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.