toggle bolt(An externally threaded fastener whose threaded portion is of one nominal diameter having a wing or wings mounted on the bolt head or on a trunnion nut. The wing or wings upset when the toggle bolt is inserted in a constricted passage in a hollow wall and when the bolt is tightened, the wing or wings assume a transverse or athwart position. It is used for securely holding fixtures or devices to hollow walls. LyuFi)
