Etymology and distribution of 研.

The Japanese surnames etymology dictionary.
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在日通名大全

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「研」さんの名字の分布数。

カンマ区切りで複数の名字を指定できます。

Etymology of 研

Distribution of 研
Ranking
1 Nakatsu-shi(About 20)
2 Nishinomiya-shi(About 10)
3 Kyouto-shi Nakagyou-ku(About 10)
3 Kure-shi(About 10)
3 Ama-gun Kanie-chou(About 10)
6 Kyouto-shi Kita-ku(Very rare)
6 Kyouto-shi Higashiyama-ku(Very rare)
6 Amagasaki-shi(Very rare)
6 Koube-shi Tarumi-ku(Very rare)
6 Mobara-shi(Very rare)
6 Kawaguchi-shi(Very rare)
6 Sakai-shi(Very rare)
6 Habikino-shi(Very rare)
6 Gojou-shi(Very rare)
6 Sendai-shi Wakabayashi-ku(Very rare)
6 Higashiusuki-gun Kadogawa-chou(Very rare)
6 Aki-gun Fuchuu-chou(Very rare)
6 Oobu-shi(Very rare)
6 Chikujou-gun Yoshitomi-machi(Very rare)