state in Shandong province
郕 is a historical place name referring to a state in ancient China, located in what is now Shandong province. Its meaning is limited to this specific geographical reference.
郕 combines 成 (which may contribute sound) with the city/walled-town component ⻏, indicating a place name. The exact historical development is uncertain.
The left side 成 suggests completion or achievement, and the right side ⻏ is a city wall. Picture a completed walled city: the ancient state of 郕.
For セイ, imagine the ancient state's name being pronounced like the English word 'say': 'Say' -> セイ, as if you are telling someone to say the name of the state.
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