Glossary Of Terms

Auxiliary Bolt

An additional bolt which is activated by the strike when the door is closed, automatically dead latching the latch bolt against end pressure. 

Back Check

The feature of a door closer unit that prevents shock and possible damage when the door is forcibly opened.


The horizontal distance from the face of the lock to the centre line of the cylinder, key hole or knob hub.

Construction Keying

System used to allow contractors to gain entry to a building during construction but to prevent entry by the same contractors after the building has been occupied or handed over. 


A bolt which is not activated by a spring. When locked the bolt cannot be returned by end pressure.


A lock containing a dead latch bolt.

Deadlatch Bolt

A spring actuated bevelled latch bolt which operates in conjunction with an auxiliary bolt which automatically locks the latch bolt against return by end pressure.


Prevents the latchbolt being manipulated open when the door is closed.


A lock incorporating a deadbolt.

Deadlocking Latch

A lock with a spring-actuated latch bolt. When the door is closed, the key or turn knob is operated to deadlock the latch bolt against return by end pressure.

Delayed Action

A feature of a door closer which holds the door in the open position for a number of seconds before the closing action commences. This feature is ideal for use by the handicapped, the aged and people with prams, trolleys, etc. The SAA Fire Door code approves the use of delayed action closers on fire doors.

Door Furniture

Fittings complimentary to the lock systems, such as handles and escutcheon plates.

Door Hardware

A general term for all types of products that may be fitted to a door such as hinges, kick plates, door closers and door stops.

Dual Select

A registered Lockwood trademark of an innovative feature which allows two stage external locking - safety mode and secure mode.

Dummy Trim

A non-operating door trim which is installed for appearance or as a door pull only.

Flush Bolt

A door bolt so designed that when installed, it is flush with the face or edge of the door.


The direction of door travel (swinging or sliding) and the locking/secure side of a door, eg. Right hand (opening out), left hand (opening out).

Hold Back

A catch or other device on a lock which can hold the latch bolt in the retracted position.

Hold Open

The feature of a door closer unit which enables a door to be held in the opened position until released.

Key in Knob/Key in Lever

Various locking and latching functions operated by a knob or lever complete with a cylinder or turnknob, incorporated within the knob/lever.

Key Locking

Indicates that operation of the key locks or unlocks the furniture and/or the bolt of the lock.

Keyed Alike

Indicates identical key for 2 or more locks.

Keyed to Differ

A different key is needed to activate each lock. 


The fastening on a door that fits into the notch or slot on a door jamb and is lifted or retracted from either side by the handle.


A spring actuated, bevelled bolt usually operated by door furniture.


A door fastening mechanism, comprising of latch, strike and door furniture.

Lock Alert

Lockwood's patented status indicator that shows the lockset mode at a glance. The lockset can operate in three modes: Secure Mode, Safety Mode and Passage Mode.


A lock, complete with strike and door furniture, such as knobs, levers, escutcheons, or handles.

Maison Keying

A keying system suitable for apartments, flats, offices, hotels and motels. Each apartment, flat or office has its own key which will not operate the locks to another apartment, flat or office but will, however, operate the locks to communal entrances and service areas.

Master Key

A key which will operate a group of locks, each built to operate on a different service key.


An opening made to receive a lock or other hardware. Also the act of making such an opening.

Mortice Lock

A lock designed to be recessed into the edge of a door, rather than being mounted to its surface.


A lock with a spring-actuated latch bolt.

Non Handed

The ability to reverse the product or key component to suit left or right-hand installation.

One Way Screw

Screws with specially shaped heads to prevent removal by conventional screwdriver.


A sliding bolt lockable by a padlock.


A small, portable lock consisting of a case containing a lock mechanism, a shackle or U-shaped bar that fastens into the lock case, and usually requires a key to open the locking mechanism.

Passage Set

A term commonly used to describe a latch set with handles on both sides of a door but no locking function.


Polyester-based coating for aluminium products providing a smooth colour finish.

Privacy Set

A term for locks used on bathroom and bedroom doors having an inside button or turn knob to lock the outside handle and usually an emergency function which will unlock the set from the outside.

Project Keying

See Construction Keying

Rebated Door

A door where the leading edge is stepped.

Rebated Lock/latch

A lock which has the faceplate and strike shaped to match the rebated edge of a door, usually the meeting edges of two door leaves.

Rim Lock

A lock or latch which is mounted to the surface of a door, rather than inserted into the edge of the door.

Safety Release

A function that automatically unlocks the internal knob upon entry. This minimises the risk of being locked inside in the case of an emergency.


A device used to either lock or unlock the lockset.


The drive shaft that connects the knob or lever to the latch or lock mechanism to operate the bolt.


A device fixed in or on a doorjamb into which the lock or latch bolt engages when the door is closed.

Tubular Bolt/Latch

A bolt having a tubular case.

Tubular Lock

A lock which has a tubular shaped case and requires bored (round) holes rather than a chiselled rectangular mortice.


Turning mechanism that activates the door lock from the inside, a convenient locking option in place of a key.

Vestibule Function

A term used to describe a lockset which is able to be opened with a key from the outside while always providing free egress.