Top Ten Locksmith Glossary Terms | Mr. Locksmith Training

To see the Complete List of Locksmith Glossary Terms to

The following Locksmith terms can change with what your locksmith speciality is from Residential, Commerical, Safe, Instutional Locksmith, etc. However, these top 10 Locksmith Terms are found on most locksmith exams. (I actually chose 25 Locksmith Terms for the Locksmith Glossary).

  1. ANSI: American National Standards Institute, Inc.
  2. Backset: The distance from the vertical centreline of the leading edge of a door to the centerline of the lock cylinder measured horizontally.
  3. Bible: The portion of the cylinder shell that normally houses the pin chambers, especially those of key- in-knob cylinders or certain rim cylinders. Note: This is on most locksmith exams.
  4. Bit: The part of the key that serves as the blade; usually for use in a warded or lever tumbler lock. Bit Key: A key with one or more projecting bits.
  5. Bitting: The number(s) that represent(s) the dimensions of the key cuts OR the actual cut(s) or combination of the key.
  6. Building Master Key: A key that operates all or most master keyed locks in a given building.
  7. Change Key: A key that operates only one cylinder or one group of keyed-alike cylinders in a keying system OR any device used to mechanically or electronically allow resetting of certain key or combination locks. (See also “Reset Key”)
  8. Control Key: A key with a sole purpose to remove and/or install an interchangeable or removable core OR a bypass key used to operate and/or reset some combination type locks OR a key that permits disassembly of some removable cylinder locks.
  9. Cut Key: A key that has been bitted or combinated.
  10. Deadlatch: A spring latch designed with an anti-shim feature that resists attempts to push it back into the retracted position when the door is closed and the deadlocking feature is activated by its position in the strike.
  11. Depth Key Set: A set of keys used to make a code original key on a key duplicating machine to a lock manufacturer’s given set of key bitting specifications. Each key is cut with the correct spacing to one depth only in all bitting positions, with one key for each depth.
  12. Direct Code: A designation assigned to a particular key that includes the actual key combination. Also see “InDrect Code”
  13. Fence: A projection on a lock bolt which prevents movement of the bolt unless it can enter gates of properly aligned tumblers OR any locking element other than a sidebar or shackle designed to enter a tumbler’s gate.
  14. Gate: A notch cut into the edge of a tumbler to accept a fence or sidebar.
  15. Hand of Lock: The right or left hand the lock is presently set to, or what hand is required.
  16. KA: (abbr.) Keyed alike
  17. Non-Fail Safe: See Fail Secure
  18. Para centric: Of, or pertaining to, a keyway with one or more wards on each side projecting beyond the vertical center line of the keyway to hinder picking OR of, or pertaining to, a key blank made to enter such a keyway.
  19. Shear Line: A location in a cylinder at which specific tumbler surfaces must be aligned, removing obstruction(s) which prevent the plug from turning.
  20. Shoulder: Portion of a key blank that normally forms the stop.
  21. Spline Key: A small part that fits snuggly into a hole formed by grooves in two mating parts, securing them together. Spline keys are commonly-used in combination locks, to secure the dial spindle to the drive cam.
  22. UL – Underwriter’s Laboratories: A chartered not-for-profit organization to establish, maintain, and operate laboratories for the examination and testing of devices, systems and materials to determine their relation to hazards to life and property, and to ascertain, define and publish standards, classifications and specifications for materials, devices, products, equipment, constructions, methods, and systems affecting such hazards.
  23. Warded Key: A key with ward cuts only; typically a bit key, flat steel key or corrugated key.
  24. Wheel Pack: A complete set of tumbler wheels, spacing washers, tension washers, etc. for a combination lock.
  25. Zero Bitted: Of, or pertaining to, a cylinder that is, or is to be, pinned to keys cut to the manufacturer’s reference number “0” bitting.

Hundreds if not thousands of Locksmith Term to be added to the Locksmith Glossary.

Retainer bolts 2nd

Parts of a Mortice Cylinder

Parts of a Mortice Cylinder


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