失しっ着ちゃくしっちゃくMeanings1nounmistake; blunder; negligenceRefers to an error or oversight, often implying a failure to pay proper attention. Used in formal or written contexts.彼かれの失しっ着ちゃくが原げん因いんでプロジェクトが遅おくれた。The project was delayed due to his mistake.この報ほう告こく書しょには重じゅう大だいな失しっ着ちゃくがある。There is a serious oversight in this report.