mountain in Henan, surname
嵇 is a proper-noun kanji used primarily as a surname and as the name of a specific mountain in Henan. Its meaning is tied to those references rather than to a general concept.
嵇 combines 山 (mountain) with a phonetic element that includes 禾 and 尤. The character was likely created to write the surname and the mountain name, with 山 providing the semantic link to the mountain.
The mountain 山 sits above a combination of grain 禾 and a bent figure 尤, as if marking a specific mountain named after the Ji clan. Picture a mountain with a sign bearing the surname 嵇.
For ケイ, imagine a mountain named after a person called Kay: Kay -> ケイ, and the mountain 山 is the Kay family mountain.
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