One and only; unique — something singular with nothing else equal to it; used to describe something highly distinctive.
彼女の作品は唯一無二の個性を持っている。
Her work has a unique character unlike any other.
その景色は唯一無二で、二度と同じものは見られないかもしれない。
That view is unique; you may never see the same thing twice.
あの店は地域にとって唯一無二の存在だ。
That shop is a one-of-a-kind presence for the community.