Kunlun mountains in Jiangsu
崐 refers specifically to the Kunlun mountain range in Jiangsu, a proper geographic name. Its meaning is tied to that location rather than a general concept.
崐 combines 山 (mountain) with 昆, which likely provides the sound コン. It is a phono-semantic compound used for the place name Kunlun.
The mountain radical 山 on the left marks this as a mountain name. The right side 昆 suggests the sound, so picture the Kunlun peaks rising beside the familiar shape of 昆.
For コン, think of the Kunlun mountains themselves: the first syllable 'Kun' sounds like コン, tying the reading directly to the place name.
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