Etymology and distribution of 貞久.

Sadahisa 【貞久】^{レベル3
About 110}  The Japanese surnames etymology dictionary.

Saga-ken Karatsu-shi , Fukuoka-ken .

① Topography . From the white passport. Saga-ken Karatsu-shi Kashiwazaki is based. Nagasaki-ken Nagasaki-shi , Fukui-ken Obama-shi was in the Edo period.

② Abstract . Synthesis of Shiraishi and Tsuda. Miyagi-ken Sendai-shi Aoba-ku Kawauchi was in the Edo era in the Sendai Samurai of the Clan office. Tsuda's character of "Tsu" who was a long-lived family because Mr. Shiraishi of the same samurai was a short-lived family, was given to the Edo period from the same lord, Tadashi Date. 白石 Shiraishi reference. 津田 Tsuda reference.