The bar between door handles is called a spindle.
The spindle or bar between the door handles is a length of square rod or bar that is made from metal that connects 2 door handles or door knobs together on either side of the door.
The spindle locates into square shaped holes found at the back of the door handles or door knobs.
When it comes to double doors, the metal bar running vertically between them is called a mullion.
This term is commonly used in the door industry, and it refers to a vertical or horizontal element that separates and supports panes of glass, as well as sections of metal or wood.
An astragal on a door is a molding or strip that is used to close gaps in a door opening.
They can be used to cover the space between a pair of doors, between the top of a door and a flush transom panel where there is no mullion, or between the top and bottom leaves of a Dutch door.
Door bars are solid strips of material, usually made from metal or wood, that sit over the gap in your doorway to create a smooth transition from one room of your home to another.
An exit device sometimes called a panic device or a crash bar is mechanical door hardware operated from the inside of an outswing exit door through the use of a crossbar or push rail and extends at least halfway across its width.
The strike plate is the portion of a lock that is secured to the door jamb and accepts the lock bolt.
Spindle- Located in the middle of any doorknob's inner workings is where the spindle, a short bar, operates the two handles and holds the knobs together.