This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
嵡 combines 山 (mountain) with 翁, but the exact historical development and original meaning are uncertain.
The top is 山 (mountain) and the bottom is 翁 (old man). Picture an old man on a mountain, but the meaning of the kanji itself remains unclear.
For オウ, imagine the old man on the mountain saying 'Oh!' as he reaches the peak: Oh -> オウ.
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