doze off, sleepy
瞌 centers on the state of being drowsy or nodding off, describing the act of dozing or feeling sleepy.
瞌 combines 目 (eye) with 盍, which likely contributes the sound and may relate to closing or covering, suggesting eyes closing in sleepiness.
The left side is an eye 目, and the right side 盍 looks like a lid covering a dish. Picture your eyelids becoming heavy like a lid, slowly closing as you doze off.
For コウ, imagine a sleepy person nodding off during a long, boring lecture: the sound of a soft snore 'kooou...' cues コウ while their eyes close.
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