Etymology and distribution of 貞岡.

Sadaoka 【貞岡】^{レベル4
About 600}  The Japanese surnames etymology dictionary.

Toyama-ken , Hokkaidou , Oosaka-fu . Terrain . From cedar and forest. Toyama-ken Toyama-shi Honmaru was in the Edo period in the clan of Toyama of the Clan office. Toyama-ken Toyama-shi Cedar forest of Nagaoka's small figure is a place name unknown in the record era. Toyama-ken Toyama-shi Mizuhashi It is a place name with a record since the Edo period. It was in the Edo period in the same place. Toyama-ken Toyama-shi Yao-cho Oosugi is a place name with a record since the Edo period. It is distributed in the same place.

Teioka 【貞岡】^{レベル4
About 600}  The Japanese surnames etymology dictionary.

Kanagawa-ken , Saitama-ken , Toukyou-to .

① Topography . From lotus and river. Saitama-ken Han'nou-shi It is distributed in Yanagi-machi.

② Korean type . Chiba-ken Sanbu-gun Yokoshibahikari-machi (formerly Yamashida-gun, Yokhiba Town) had a name in 1980. The real name is Li. Kanagawa-ken Yokohama-shi There is a record of naturalization on March 18, 1986 in Naka-ku. The real name is Li. 李 Ri reference.