name of a Chinese river
淮 is a proper noun referring to the name of a Chinese river, the Huai River. It has no broader conceptual meaning beyond this specific geographical reference.
淮 combines the water radical 氵 with 隹, which likely contributes the sound. It is a phono-semantic compound created specifically to name the Huai River.
The water radical 氵 on the left signals a river, and the right side 隹 gives the sound. Picture the Huai River flowing beside a distinctive bird-shaped rock that looks like 隹.
For ワイ, imagine the Huai River winding like a Y: the letter Y sounds like ワイ, and the river's shape matches.
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