一いっ線せん級きゅう

noun which may take the genitive case particle 'no'

top-notch; first-rate; leading

Describes something of the highest quality or rank, often used for products, services, or people. Functions as a no-adjective modifying a noun.

• 彼かれは一いっ線せん級きゅうのエンジニアだ。

  He is a top-notch engineer.

• このホテルは一いっ線せん級きゅうのサービスを提てい供きょうしている。

  This hotel provides first-rate service.