陡
doǔ · HSK 7
steep
⛰️ Sounds like DOUbt — you doubt you can climb something this steep
Left side is earth radical (阝hill), right is walk (走). A hill so steep you doubt every step. The DOUbt sound locks in the dǒu pronunciation.
陡 — 阜 mound radical 阝 + 走 run/walk
陡 combines the mound/hill radical 阝 (left form of 阜) with 走 (to run/walk), suggesting a slope so steep one must scramble. 走 also hints at the sound. The original sense was a sudden, sharp incline, which broadened to mean 'steep' and figuratively 'abrupt' or 'sudden'.