濫用
らんよう · ranyou · JLPT N1 · noun
maltreatment
🪓 濫 = overflowing water + 用 = use: water spilling past its banks is use gone to excess
濫 (らん) means overflowing or flooding, as a river bursts its banks. 用 (よう) is use. Overflowing use equals misuse: 濫用 means using something beyond what is proper or needed.
用 — pictograph of a bucket or wooden pail
用 originally depicted a bucket or container, possibly a sacrificial vessel made of wood. Over time it was borrowed to mean 'to use' or 'employ,' losing its concrete object sense. The modern meaning 'use' has been standard since early classical Chinese.