The kanji 睡 primarily conveys the idea of sleep or drowsiness. It represents the state of being unconscious, resting, and typically associated with dreams. It can also imply a state of calmness and relaxation, often related to the absence of active awareness.

・On-yomi (音読み): スイ (sui) ・Kun-yomi (訓読み): ねむ（る） (nemu(ru))

⚫︎ 睡眠 Translation: Sleep ⚫︎ 昼睡 Translation: Napping (daytime sleep) ⚫︎ 睡魔 Translation: The Sandman (personification of sleepiness)

The kanji 睡 is a phono-semantic compound (形声文字, けいせいもじ). ⚫︎ The semantic component is 目 (め, me), meaning "eye". ⚫︎ The phonetic component is 卒 (そつ, sotsu) or a similar sound, which conveys the sound "sui". The original form may depict an eye that is closed, or the situation of one's eyes being closed while sleeping. This visual representation evolved into the kanji we know today, associating it with the concept of sleep.