This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
咃 is a rare character. It visually combines 口 (mouth) with 他, but the exact historical development is uncertain.
The left side is a mouth 口, and the right side is 他 (other). Without a clear meaning, picture a mouth speaking about something other, but treat the meaning as uncertain.
For タ, imagine a mouth 口 saying 'ta!' as it points to another 他 person: ta -> タ.
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