name of a Chinese river
淇 is a proper noun referring to a specific Chinese river. Its meaning is limited to this geographic name.
淇 combines the water radical 氵 with the phonetic component 其, forming a character used as a river name. The exact historical development is uncertain.
The water radical 氵 beside 其 suggests a river. Picture a map where the 其 shape marks the winding path of the Qi River.
For キ, imagine a key floating on the river: key -> キ, and the key unlocks the name of the Qi River.
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