Etymology and distribution of 五岩.

Goiwa 【五岩】^{レベル1
Very rare}  The Japanese surnames etymology dictionary.

Mie-ken Ise-shi , Oosaka-fu . Thing . From the pole that advances the ship. In Mie - ken Ise - shi Futami - machi tells that he was a polemaker at Shichinomiya Shrine located in the same place and was renamed from Teramoto surname at the Meiji New surname. 寺本 Teramoto reference.