Locksmith Terms Glossary M-P
- master key A key which will open every lock in the 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.
- mortise 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 to let into the thickness of the door from the meeting edge and held in position by screws through the forend.
- narrow case lock or latch A rim lock or latch, the case of which is made specially narrow, usually less than three inches wide, for fixing to the narrow stile of a panelled or flush door.
- nightlatch A rim or mortice latch with a bevelled springbolt or roller bolt which shoots when the door is closed, but can be withdrawn by key from outside and by knob or lever handle from inside.
- nozzle A circular boss or ferrule containing the keyhole on some cabinet locks, including locker locks. Correctly relating to lever cabinet locks.
- one-sided lock (single-entry) A lock which has a keyhole on one side only.
- one-way action An action where the follower will turn only one way.
- pan The removable mechanism chamber attached to the inside face of a safe door.
- panel grilles Steel grilles made to size with various infills of expanded diamond mesh, square weldmesh or fancy infills, usually fitted internally.
- peg ward A combination of wards resembling a sash ward but fixed by pegs to the lock case.
- pins Usually the lower of each pair of tumblers in the pin tumbler cylinder mechanism. The upper are known as drivers.
- pin stack The combination of a lower pin sitting beneath an upper pin. In master keyed locks, additional master pins may be located between the lower and upper pins.
- pin tumbler mechanism The mechanism incorporated in the cylinder or body of a cylinder pin tumbler lock, latch or padlock.
- pipe key A key with a flat bit and a hollow circular shank to locate on the drillpin. Used only on one-sided locks.
- plug The part of the lock that you put the key into, and which turns to operate the lock.
- pre-assembled lockset A lock designed to be installed into a cutout in the edge of a door. The lock body and most or all of its trim need no further assembly other than securing it to the door.