細ほそい糸いと

expression, noun

fine thread; thin thread

Refers to a physically slender thread or string. Can be used literally or metaphorically (e.g., a slender connection).

• 細ほそい糸いとでボタンを縫ぬい付つけた。

  I sewed the button on with fine thread.

• 彼かれらの友ゆう情じょうは細ほそい糸いとでつながっているようだ。

  Their friendship seems to hang by a thin thread.