唇しん歯し

noun

lips and teeth

Literal meaning referring to the body parts. Often used in set phrases or classical contexts.

• 唇しん歯しの間あいだから冷つめたい空くう気きが漏もれた。

  Cold air leaked from between his lips and teeth.

noun

mutually dependent relationship

Figurative use based on the idea that lips and teeth are interdependent; often appears in the idiom 唇歯輔車 (しんしほしゃ) or similar classical expressions.

• 両りょう国こくは唇しん歯しの関かん係けいにあると言いわれる。

  The two countries are said to have a mutually dependent relationship like lips and teeth.