place name
崑 is a kanji used primarily in proper nouns, especially the place name 崑崙 (Kunlun). Its standalone meaning is tied to that mountain range and has no independent everyday sense.
崑 combines 山 (mountain) with 昆, which likely contributes the sound. The character was created to write the name of the Kunlun mountains.
The mountain 山 on top of 昆 points to a specific mountain range. Think of 崑 as the mountain that sounds like 昆.
For コン, picture a con artist trying to sell you a fake map to the Kunlun mountains: con -> コン, and the mountain 山 is right there on the map.
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