Locksmith Glossary

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Appendix



abb. sub-assembled
n. a substantial, secure container with varying degrees of security and/or fire resistance, used to store valuables against fire or theft
safe deposit
n. a typically key accessed container that requires dual key operation, usually located inside a vault
safe door
n. that portion of a safe used to gain access to the contents of the safe in a normal day to day manner
sally port
n. an access control area with doors or gates secured by interlocks such that only one may be opened at a time
abb. Safe and Vault Technicians Association
abb. Southern Building Code Congress International
n. a thin piece of metal which is usually crimped or spun onto the front of a cylinder. It determines the cylinder's finish and may also serve as the plug retainer.
Scandinavian padlock
n. a cast case padlock with an elliptical cross section. The locking mechanism is a set of rotating disc tumblers, which engage notches in the cast shackle and may be rotated by the angled cuts cast on the key.
screen door lock
n. a lock designed for the thin stiles typically found on screen and storm doors
screw change (wheel)
n. a perforated tumbler that may have its combination set by placement of a screw in one of the perforations
screwless knob
n. a mortise lock knob assembly secured to the spindle without screws
screwless rose
n. a mortise lock rose installed without screws
abb. safe deposit box
n. a single use device intended to give recognizable evidence to the physical opening or entry of a door, container, or space
second generation duplicate
n. a key reproduced from a first generation duplicate
secondary key
n. a key which operates certain locks on a vehicle, but not the ignition lock
secret gate latch
n. a small keyless rim latch, which when properly installed, is operated by pressing a concealed actuator
sectional trim
n. a design that uses two or more escutcheons on the same side of a door for a single lock
security collar
n. 1. a protective cylinder collar, see also "cylinder guard"
security leg keyway
n. a key section and keyway design that incorporates two non-curved planes of the key blade intersecting at an angle between 1 and 89 degree
segmented follower
n. a plug follower sliced into sections which are introduced into the cylinder shell one at a time. It is typically used with profile cylinders.
selective key system
n. a key system in which every key has the capability of being a master key. It is normally used for applications requiring a limited number of keys and extensive cross keying.
selective master key
n. an unassociated master key which can be made to operate any specific lock(s) in the entire system in addition to the regular master key(s) and/or change key(s) for the cylinder without creating key interchange
self closing
adj. pertaining to doors or covers which have a continuous force applied in the closing direction
semi-automatic key machine
n. a machine capable of duplicating keys with limited manual operations
sequence of progression
n. the order in which bitting positions are progressed to obtain change key combinations
series wafer
n. a type of disc tumbler used in certain binary type disc tumbler key-in-knob locks. Its presence requires that no cut be made in that position on the operating key(s)
serrated fence
n. a fence with "V" shaped notches on a contact surface to inhibit manipulation
serrated tumbler
n. 1. a disk tumbler with "V" shaped notches in its sides that do not allow operation, 2. a lever tumbler which has "V" shaped notches in the contact end near the gate, 3. a pin tumbler with "V" shaped grooves around its circumference, 4. a combination wheel with "V" shaped notches along its outside diameter
service code
n. in an electronic lock, a factory set or user set code or combination that will open the lock one time
service hole
n. 1. an aperture aligned with each chamber, providing a path for the ejector pin to drive the entire pin stack from an IC, 2. a hole in a cylinder shell intended to provide access for rekeying without disassembly of the cylinder
service panel
n. the back cover of a safe door which must be opened or removed to allow access for repairs
servicemark keyway
n. any keyway whose shape has been configured to receive protection under trademark or servicemark law
set screw
n. a screw used to fasten a component in a fixed position relative to another component
set-up key
n. a key used to calibrate some types of key machines
set-up plug
n. a type of loading tool shaped like a plug follower. It contains pin chambers and is used with a shove knife to load springs and top pins into a cylinder shell.
seven column progression
n. a process wherein key bittings are obtained by using the cut possibilities in seven columns of the key bitting array
seven pin master key
n. a master key for all combinations obtained by progressing seven bitting positions
sex bolt
n. a nut and bolt set used to through bolt, with a closed nut basically flush with the mounting surface creating the appearance of a carriage bolt
abb. Small Format Interchangeable Core
n. 1. the part of a padlock, which passes through an opening in an object or fits around an object and is ultimately locked into the case 2. the portion of a restraint which fits around the wrist, ankle, neck, waist or thumb
shackle retaining pin
n. a pin which keeps an unlocked shackle heel in the case
shackle spring
n. a spring which pushes the shackle into the open position when the padlock is unlocked
n. 1 the part of a bit key between the bow and the stop; or, if there is no shoulder stop, the part between the bow and the near side of the bit, 2. a smaller diameter portion of a knob that is positioned between the larger portion of the knob and the rose or the door surface
abb. Security Hardware Distributors Association (formerly NLSA)
shear line
n. a location in a cylinder at which specific tumbler surfaces must be aligned, removing obstruction(s) which prevented the plug from moving
n. the part of the cylinder which surrounds the plug and which usually contains tumbler chambers corresponding to those in the plug
1. n. a thin piece of material used to unlock the cylinder plug from the shell by separating the pin tumblers at the shear line, one at a time 2. v. to unlock a cylinder plug from its shell by using a shim
n. 1. a bracket which attaches the arm of a door closer to the door or frame 2. the surface mounted case and guide components of an exit device 3. a mortise lock component which transfers pivoting motion of a thumbpiece to linear movement of the latch bolt
n. any key stop other than a tip stop, see also "bow stop"
shouldered chamber
n. a pin chamber with an internal shelf that limits travel of a complementarily shaped bottom pin
shouldered pin
n. a pin tumbler shaped as to prevent it from fully entering an unoccupied keyway or limit its travel within a pin chamber
shouldered spindle
n. in a safe lock, a spindle with a larger uniform diameter toward outside to prevent punching the spindle into the container
shove knife
n. a tool used with a set-up plug which pushes the springs and pin tumblers into the cylinder shell
showcase lock
n. normally a ratchet lock or plunger lock used on bypassing doors
shrouded shackle
n. a shackle which is protected from cutting or tampering by design or by the use of secondary shields
shunt switch
n. a maintained contact switch, often key operated
shut out key
n. usually used in hotel keying systems, a key which will make the lock inoperative to all other keys in the system except the emergency master key, display key, and some types of shut out keys
shut out mode
n. the state of a hotel function lockset which prevents operation by all keys except the emergency master key, display key, and some types of shut out keys
n. 1. a spring-loaded device which closes upon the removal of a cylinder tailpiece, protecting a locking device from being manipulated, 2. a spring-loaded device which covers a cylinder keyway when the key is not in it, also see appendix
shutter spring
n. a spring which returns the shutter on a lock to the closed position
sickle key
n. a key in the form of a sickle inserted through a hole in a door to actuate a bolt on the opposite side of the door
side milling slotter
n. a key machine cutting wheel with a squared edge that can cut on the side as well as the periphery of the wheel
side sheath
n. a portion of a multi-part pin tumbler lock plug used to complete the shear line fully around the plug
side ward
n. a ward which prevents entry of an incorrect key into a non-cylinder lock
side ward cut
n. a cut made into a key to bypass a side ward
n. a cylinder component which enters gate(s) in tumbler(s) to allow plug rotation
sidebar lock
n. a lock mechanism which incorporates a sidebar
sidecode variant
n. a master keying style of pin tumbler locks which uses the keying capabilities of the secondary security technology to effect master keyed locking. Obtaining a single key in the system does not reveal the same secondary combination of all keys.
sidewinder key
n. typically an automotive key with a bitting(s) milled into the widest side(s) of the key blade with an end milling cutter
silent signal
adj. describes an alarm that annunciates detection to a remote location instead of a local location
simple latch
n. a non-deadlocking latch
simplex key section
n. a single independent key section which cannot be used in a multiplex key system
simultaneous retraction
n. a feature which allows retraction of both the deadbolt and latchbolt in the same operation
single acting (door)
n. a door which swings from the latched position in only one direction
single-acting lever tumbler
n. a lever tumbler which must be moved a minimum distance to allow travel of a bolt, but cannot be moved so far as to restrict travel of the bolt
single cylinder
adj. pertaining to a lock with key operation from only one side
adj. the shape of a cutout for a lock, circular except for a flat section on one side
single key section
n. an individual key section which can be used in a multiplex key system
single step progression
n. a progression using a one increment difference between bittings of a given position
six column progression
n. a process wherein key bittings are obtained by using the cut possibilities in six columns of the key bitting array
six pin master key
n. a master key for all combinations obtained by progressing six bitting positions
abb. standard key coding system
sym. symbol for "single keyed", normally followed by a numerical designation in the standard key coding system; e.g., SKD1, SKD2, etc. It indicates that a cylinder or lock is not master keyed but is part of the keying system
skeleton key
n. any non-cylinder key whose bit, blade, and/or post is cut away enough to allow it to enter and turn in locks with different ward arrangements
slide hammer
n. a tool made from a rod with a handle, a sliding weight on the rod, and a means of attaching to a part to force its movement relative to other parts
n. a tumbler which is normally flat, has a gate and moves with a linear or lateral motion instead of pivoting like a lever tumbler
slim jim
n. a narrow strip of spring steel used to bypass the cylinder and unlock vehicle doors
n. a cable or layered length of fabric, (usually the latter), with woven loops in both ends, used to lift a safe or vault door with a boom arm lift or forklift.
n. a key machine cutter designed to make cuts with a rectangular shape
Small Format Interchangeable Core
n. an IC that replicates the functionality and design popularized by Best
n. a card conforming to ISO specification 7810 and 7816 which one or more integrated circuits with contacts allowing interface to external equipment
abb. sub-master key
abb. Safe Manufacturers' National Association
adj. referring to an area or opening protected against the penetration of smoke
snap bow
n. 1. a separate bow which can be affixed to a smaller key bow, 2. a bow which retrofits transponder technology to conventional keys for use in access control systems
software key
n. data used by software to provide or deny access. See also 'hardware key'
n. the dimensions from the stop to the center of the first cut and/or to the centers of successive cuts
spanner wrench
n. a tool for installing, removing or adjusting a threaded part. The tool is designed to engage one or more holes or depressions which are peripheral or not on-center to the part axis. 
spare tire lock
n. a lock designed to prevent removal of a vehicle's spare tire
special application cylinder
n. any cylinder other than a mortise, rim, key-in-knob or profile cylinder
n. a component which transfers rotary motion from outside a lock or latch case to an inner mechanism
n. a groove in a combination lock spindle designed to accept a spline key
spline key
n. a device inserted to position the drive cam relative to the spindle in a combination lock
spline way
n. a notch in a combination lock drive cam designed to accept a spline key
split bolt
adj. two separate bolts housed in the same opening in a face of a lock, each operated independently from opposite sides of the door
split finish
adj. of or pertaining to a lockset whose finish is different on each side of the door
split hub
n. a two-piece hub which can allow motion from one side of a swivel spindle while preventing it from the other side
split pin master keying
n. a method of master keying a pin tumbler cylinder by installing master pins into one or more pin chambers
split spindle
n. a multi-piece spindle which allows a knob or lever to be installed on only one side of a door
split wafer
n. Disc tumblers which are approximately half the width of a full tumbler used in the same lock, and are paired adjacent to one another in the same cut position. Typically used in automotive locks.
spool pin
n. usually a top pin which resembles a spool, typically used to increase pick resistance
spring cover
n. a device for sealing one or more pin chambers
spring hinge
n. a hinge incorporating a mechanism to apply automatic closing force 
spring latch
n. a latch operated under spring pressure, having no deadlatching feature
spring seat
n. the point at which a spring is anchored, located or attached and at which (from which) it exerts force
spy-proof dial
n. a dial and dial ring that complement each other to limit viewable numbers to a range of approximately 10 at a time
square back
adj. pertaining to a rim cabinet lock whose mounting flanges and case form the general shape of a square
stand alone
n. a self contained electronic lock device
standard key coding system
n. an industry standard and uniform method of designating all keys and/or cylinders in a master key system. The designation automatically indicates the exact function and keying level of each key and/or cylinder in the system, usually without further explanation.
standard progression format
n. a systematic method of listing and relating all change key combinations to all master key combinations in a master key system. The listing is divided into segments known as blocks, horizontal groups, vertical groups, rows, and pages, for levels of control.
n. a set of specifications relating to materials, finishes, construction, resistance, or strength that typically establish a minimum acceptable value
n. the portion of a hasp assembly with the hole or opening to receive a padlock
step pin
n. a spool or mushroom pin which has had a portion of its end machined to a smaller diameter than the opposite end. It is typically used as a top pin to improve pick resistance by some manufacturers of high security cylinders.
stepped tumbler
n. a special (usually disc) tumbler used in master keying. It has multiple bearing surfaces for blades of different key sections.
n. the vertical construction member located on either edge of a door
stop (of a door)
n. the projecting portion of a doorframe upon which the door rests when closed
stop (of a key)
n. the part of a key from which all cuts are indexed and which determines how far the key enters the keyway
stop gauge
n. the part of a key machine that aligns a key blank, a pattern key, or both, so that the blank may be cut correctly
stop works
n. a button or toggle mechanism which prevents operation of a knob, lever or thumbpiece in a non-bored lock
stop works button(s)
n. a one or two-piece stop works activator
store door function
n. a lockset function in which: a) a deadbolt is operated by key from either side and a latch is operated by working trim from either side; or b) a deadlocking latch can be withdrawn by working trim from either side except when both sides are locked by key from either side.
straight knife
n. a bypass tool for manipulating a spring bolt directly behind the cylinder plug
n. a bolt receptacle typically mounted in the door jamb or the floor
strike locator
n. a tool used to mark the jamb, relative to the bolt of the lock, prior to strike installation
strike reinforcer
n. a metal plate mounted behind a strike, using long screws to secure it to the door frame
n. the stationary fence(s) in a lever lock
sub-master key
n. the master key level immediately below the master key in a system of six or more levels of keying
substitution code
n. a code whose individual characters are converted to individual key cuts or combination numbers by means of a reference table
Suffolk latch
n. a door latch consisting of a horizontal bar which moves vertically to unlatch on the inside, actuated by a thumb piece on the outside
supervised security seal
n. a device which provides visual indication of tampering and includes the ability to be connected into electronic security systems
surface pull
n. a handle or grip attached to the surface of a door or drawer
n. the radiused part of a lever tumbler with which the key makes contact
sweep speed
n. the speed at which a closer moves a door from open to the point where latching speed is engaged
swing clear hinge
n. a hinge that allows the door to swing far enough away from the jamb to fully clear the opening at 90 degrees open
switch lock
n. 1. a lock which incorporates an electrical switch as an integral part of its construction 2. a large padlock designed for use on railroad switches
swivel spindle
n. normally a two-piece spindle assembly whose two halves are designed to turn independently

Copyright 1989, 1990, 1995, 1996, 1997, 2000, 2001, 2002 LIST Council

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Appendix