Common Terms & Glossary
You can use the information contained here to find helpful definitions of commonly used terms to aid with the selection process.
Backset
The measurement between the edge of the door to the center of the hole drilled for the lock.
Bolt
The piece of metal that protrudes and secures or closes a door.
Cylinder
The round assembly of the lock which provides the ability to lock a door through the tumbler and the keyway.
Deadbolt
A lock whose latchbolt is engaged by using a key or a thumbturn.
Fixed Interior
A term used to describe a stationary piece of door hardware that does not provide any latching function for the door.
Function
The type of door hardware used by a specific entry or door. Example “Bed/Bath”, “Hall/Closet” or “Entry”.
Locking
Both knobs locked or unlocked by outside key or thumbturn inside.
Non-Locking
Both knobs always free.
Handing
Some styles of levers are handed, usually due to a curved lever design. There are left-handed levers and righthanded levers. To determine the appropriate handing for your door, look at the hinges from the exterior side of the door. As you stand outside facing the door, if the hinges are on the left, you require a left-handed lever. If the hinges are on the right, you need a right-handed lever.
Handleset
The door hardware that encompasses a grip or handle along with a deadbolt function to lock the door.
Keyway
The area on the face of a keyed product where the key is placed.
Knobset
A door set consisting of inside and outside knobs.
Latch
The mechanism that throws the bolt or closes the door when the door is closed.
Leverset
A door set consisting of inside and outside levers.
Rose
The circular plate surrounding the knob or lever that is flush against the door.
Strike
The metal attachment that is mounted onto the doorframe.
Thumbturn/T-turn
The small knob or lever turnpiece on the inside or inner trim that operates the deadbolt function.
Throw
The measurement of the projection of a deadbolt latch.
Thumb Piece
The small moving part on the grip of a handle that is depressed when opening a handleset.