be perplexed
悗 centers on a state of mental confusion or being perplexed, where one's thoughts are tangled and unclear.
悗 combines 忄 (heart/mind) with 免, which likely contributes a phonetic element. The exact historical development is uncertain, but the structure suggests a mental state related to the sound 免.
The heart radical 忄 beside 免 (which can suggest escape or avoidance) paints a picture of a mind trying to escape confusion but only becoming more perplexed.
For バン, imagine a perplexed person banging their head against a wall in frustration: bang -> バン, and the heart 忄 is tangled in confusion.
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