frown
顣 centers on a facial expression of displeasure or worry: a frown. The meaning is narrow and concrete.
顣 combines 戚 (which can suggest distress or sorrow) with 頁 (head), pointing to a distressed facial expression. The exact historical development is uncertain.
The left side 戚 looks like a worried relative, and the right side 頁 is a head. Picture a relative's head with a deep frown of concern.
For シュク, imagine a person frowning while shaking their head: 'shook' -> シュク, as they disapprove with a frown.
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