thread the needle

Short definition from Wiktionary

Verb

1. 1
   To perform a tedious task with extreme precision; to manage to find harmony or strike a balance between conflicting forces, interests, etc.
2. 2
   To fly through a narrow gap; typically using a wingsuit.

Noun

1. 1
   A game in which children stand in a row, joining hands, and in which the outer one, still holding their neighbor, runs between the others.