凡ぼんミス

noun

basic mistake; careless error

Casual term for a simple, avoidable mistake; often used in sports, games, or everyday situations.

• 試し合あいで凡ぼんミスをして負まけてしまった。

  I made a careless mistake in the match and lost.

• こんな凡ぼんミスをするなんて、疲つかれてるのかな。

  Making such a basic mistake—maybe I'm tired.