Etymology and distribution of 忍穂井.

Oshihoi 【忍穂井】^{レベル1
Very rare}  The Japanese surnames etymology dictionary.

Toukyou-to . Variant of 鑰尼 . Toukyou-to tells you that you changed your name from Mei-Nam Surname to Hanyu Surname in Muromachi Period and made a mistake at the Meiji New surname. 鑰尼 Kagiama reference.