一いち大だい事じ

noun

important matter; serious affair; emergency

Refers to a matter of great importance, often with a sense of urgency or gravity. Used in both formal and everyday contexts.

• これは一いち大だい事じだ。すぐに対たい策さくを考かんがえなければ。

  This is a serious matter. We must think of countermeasures immediately.

• 首しゅ相しょうの辞じ任にんは一いち大だい事じとして報ほう道どうされた。

  The prime minister's resignation was reported as a major incident.