Etymology and distribution of 古子.

The Japanese surnames etymology dictionary.
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在日通名大全

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「古子」さんの名字の分布比率。

カンマ区切りで複数の名字を指定できます。

Etymology of 古子

Distribution of 古子
Ranking
1 Nakatado-gun Kotohira-chou(0.0318%)
2 Miyoshi-gun Higashimiyoshi-chou(0.0212%)
3 Saikai-shi(0.0196%)
4 Mitoyo-shi(0.014%)
5 Hidakashi-chou Shinhidaka-chou(0.0127%)
6 Zentsuuji-shi(0.0109%)
7 Shiraoka-shi(0.0102%)
8 Kyouto-shi Higashiyama-ku(0.00887%)
9 Sodegaura-shi(0.00849%)
10 Hanyuu-shi(0.00802%)
11 Imari-shi(0.00701%)
12 Munakata-shi(0.00568%)
13 Miki-shi(0.00486%)
14 Kounosu-shi(0.00394%)
15 Habikino-shi(0.00392%)
16 Oosaka-shi Higashisumiyoshi-ku(0.00376%)
17 Sapporo-shi Chuuou-ku(0.00301%)
18 Uji-shi(0.00235%)
19 Nagasaki-shi(0.0017%)
20 Ootsu-shi(0.00144%)
21 Hirakata-shi(0.00125%)
22 Hamamatsu-shi(0.00112%)
23 Amagasaki-shi(0.00107%)
24 Kurashiki-shi(0.00089%)
25 Sakai-shi(0.000572%)