It’s a hinge joint. Oh! You’ve had an idea ... A hinge has two plates called ‘leaves’ made of metal or another sturdy material. These leaves are joined in the middle by a pin that runs ...

A few weeks ago, the latch in my car door got stuck, blocking the door from closing. After a few crude attempts at jostling it, I knew it was time to purchase a silicone spray to lubricate it.