夢
ム, ボウ, ゆめ, ゆめ.みる, くら.い
dream, vision, illusion
JLPT3 G5 S13 F943
An abbreviated form# of 蔑 (obscured vision) +
夕
evening → darkness where vision is obscured → *dark* → protracted *dream* (← obscure state of being).
[Full Kanji Etymology List]