凡ぼん失しつ

noun

common mistake; elementary error

Refers to a mistake that is so basic or obvious it should not have been made; often used in self-criticism or when pointing out a careless error.

• こんな凡ぼん失しつをするなんて、自じ分ぶんが情なさけない。

  I'm ashamed of myself for making such a basic mistake.

• プロの選せん手しゅがあんな凡ぼん失しつをするとは信しんじられない。

  I can't believe a professional player would make such an elementary error.