river in Shandong province
淄 is a proper noun referring to a specific river in Shandong province. It has no broader conceptual meaning beyond this geographic name.
淄 combines 氵 (water) with 甾, which likely contributes the sound. It is a phono-semantic compound used as a river name.
The water radical 氵 beside 甾 marks this as a river. Picture the 甾 shape as a map of the Zi River's winding course through Shandong.
For シ, imagine the river's name sounds like 'she' in English: 'She' River -> シ, flowing through Shandong.
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