used in proper names, (kokuji)
屶 is a kokuji (Japan-made kanji) with no clear standalone meaning. It is used in proper names, and its meaning is uncertain.
屶 is a kokuji, likely created in Japan by combining 山 (mountain) and 刀 (sword/knife). The exact historical motivation is uncertain.
A mountain 山 with a sword 刀 at its base: picture a named mountain with a blade-like ridge, used in proper names.
For なた, imagine a mountain named Nata where a legendary sword was forged: Nata -> なた.
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