noun · a conducting wire used to connect components within an electrical circuit

由于引线接触不良，这台设备无法启动。

noun · a cord or device used to ignite an explosive or firework

他点燃了烟花的引线。

noun · a person or factor that acts as a go-between or a catalyst for an event

这次小事故成了引发大规模抗议的引线。