睡眠
すいみん · suimin · JLPT N3 · noun
sleep
🛏️ 睡眠 = 睡 (sleep) + 眠 (slumber): sleep said twice
Both kanji mean sleep. 睡 (sui) also appears in 睡魔, drowsiness; 眠 (min) is the kanji in 眠る (nemuru), to sleep. Sound hook: suimin sounds like swimmin', as in swimmin' off to sleep.
睡 — eye 目 + drooping 垂
睡 is a semantic compound: 目 (eye) signals the meaning, while 垂 (to droop, hang down) suggests eyelids falling. Together they depict drooping eyelids, i.e. dozing off. The original sense was nodding off while sitting; it later broadened to mean sleep in general.