A hinge is a simple device that allows a door or lid to swing open and closed. It acts as a flexible joint, connecting two solid objects together, so that one can move while the other stays in place. Full definition
The case he is working on hinges on the paper within, but he only aggravates the other man when he tries to retrieve it. (qwipster.net)
Lucerne International supplies the door hinges on Jeep Wranglers, like this vehicle seen at a dealership in Hollywood, Fla.. (npr.org)
Instead of hinging on ticking - clock theatrics, the tension is derived from the agonizing wait for Alice to feel enough to have the courage — even the energy — to conduct an act of defiance. (booklistonline.com)