希き代たい未み聞もん

noun, noun which may take the genitive case particle 'no'

unheard-of; unparalleled

Emphasizes that something is so extraordinary it has never been heard of before. Often used in formal or literary contexts.

• これは希き代たい未み聞もんの大だい事じ件けんだ。

  This is an unprecedented major incident.

• 彼かれの成せい功こうは希き代たい未み聞もんの快かい挙きょと言いえる。

  His success can be called an unparalleled achievement.