This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
咟 visually combines 口 (mouth) and 百 (hundred), but the historical origin and original meaning are uncertain.
With no clear meaning, picture a mouth 口 shouting a hundred 百 random words—the sound is loud but the meaning is unclear.
For カク, imagine a mouth 口 making a hundred 百 sharp 'kak' sounds: kak -> カク.
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