This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
嵹 combines 山 (mountain) with 强, but the historical development and original meaning are uncertain.
A mountain 山 with 强 underneath might suggest a strong or imposing mountain, but the actual meaning is unknown.
For キョウ, imagine a strong mountain echoing with a loud 'kyo' sound: kyo -> キョウ.
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