The following Glossary of Locksmith Terminology is provided courtesy of the Master Locksmith Association (MLA). Click on a letter below to be taken to its corresponding terms.

Master Key - A key which will open every lock in a master keyed suite.

Master Keyed (locks or latches) - A lock or latch capable-of being operated also by a master key as well as its own change or servant key.

Master Pins - Small pins sometimes called wafers to build up chamber pin loading in pin tumbler master keyed cylinders.

Mechanism (of locks or latches) - The arrangement of the component parts and the manner in which they perform to achieve the required security and differing when operated by its key. Main mechanisms include: (i) pin-tumbler, (ii) lever, (iii) discs, (iv) wards. There are other specialised mechanisms, e.g. Butters or Bramah.

Mortice - A hole cut into the thickness of one edge of a door to receive a mortice lock or latch.

Mortice lock (or latch) - A lock or latch which is morticed or let into the thickness of the door from the meeting edge and held in position by screws through the forend.

Mushroom driver - A driver in the cylinder mechanism which is tapered and has a mushroom shaped head. These provide a very effective anti-pick element, as they cannot be lifted by a lock-pick or similar item. When manipulated, the mushroom drivers tilt and wedge the plug at the line of intersection. For example, all Yale cylinder rim, cylinder mortice locks and cylinder padlocks have mushroom drivers incorporated in the mechanism.

Tel. 0800 0 187 187

e-mail: callcentre@timpsonlocksmiths.co.uk