half moon cut

n. a semi-circular cut in the bolt throw bit of a key, with the cut axis running parallel to the key shaft. Found typically on a key for a high security lever safe lock.

half mortise

1. adj. pertaining to an installation prep that typically leaves the bolt face plate and a perpendicular surface of the lock visible, with visible surfaces being flush mounted, 2. v. to make a cavity in a door or drawer that is open on the edge and on one side of the door or drawer, 3. adj. pertaining to a locking device designed to fit in a half mortise prep

half-mortise hinge

n. a hinge which has one leaf mortised into the door and the second leaf applied to the surface of the frame

half-surface hinge

n. a hinge which has one leaf mounted onto a face of the door and the second leaf mortised into the frame

hand change

adj. pertaining to a combination lock in which the wheels must be removed in order to change the combination

handed

adj. pertaining to hardware which is manufactured only for application on doors with a specific orientation

handleset

n. a complete lock or latch assembly which incorporates a pitcher handle

handicapped code

n. any building code designed to ease access for handicapped persons

hang (rake & hang)

v. to cause a top or master pin to rest on the plug when picking

hardened core (pin)

adj. a bottom or top pin which is bimetallic, the central portion of which being hardened metal intended to resist drill attack

hardplate

n. a tempered barrier placed between the lock and the outside of a safe to inhibit drilling

hard wire system

n. a system which uses metallic conductors to connect the various sensors to the central processor

hardware key

n. a computer hardware component which protects copyrights by preventing software from running on any computer where the key is not installed. The key is typically accessed via one of the ports.

hardware schedule

n. a listing of the door hardware used on a particular job it includes the types of hardware, manufacturers, locations, finishes, and sizes. It should include a keying schedule specifying how each locking device is to be keyed.

hasp

n. a hinged metal strap designed to be passed over a staple and secured in place

header

n. the horizontal, top, member of a door jamb

heel & toe locking

n. describes a padlock which has locking dogs at both the heel and toe of the shackle

heel (of a padlock shackle)

n. the part of a padlock shackle which is retained in the case when in the unlocked position

height adjustment screw

n. a screw contained within the hinge block of a safe that raises or lowers the door to clear the frame

helmet lock

n. auxiliary lock on motorcycles used to secure a helmet

HGM

abb. horizontal group master key

HiCo

abb. high coercivity

high coercivity

adj. a high energy form of magnetic encoding measuring in the range of 2400 to 4000 Oe which is resistant to accidental erasure

high security cylinder

n. a cylinder which offers a greater degree of resistance to any two or more of the following: picking, impressioning, key duplication, drilling or other forms of forcible entry

high security key

n. a key for a high security cylinder

hinge security stud

n. a protrusion on one leaf of a hinge which interlocks with the other when the door is closed

hinge stile

n. the vertical edge of a door where hinges are installed

hinged shackle

n. a shackle whose heel is permanently mounted to the padlock case in a manner which allows the shackle to pivot to open

HKP

abb. housekeeper's key

Hobbs shackle

n. a hinged shackle with a notch for the bolt in its movable end

hold open

n. 1. a function of self latching hardware which allows a lock to be set in a non-latching mode 2. A function of a door closer, or separate hardware device, which allows the door to be retained in an open position

hold open arm

n. a door closer arm with the capability of maintaining the door in the open position

hold open cylinder

n. a cylinder provided with a special cam which will hold a latch bolt in the retracted position when so set by the key

holdback

n. a function of some self latching locks which allows selective retention of the bolt to prevent latching when the door is closed

holding fixture

n. a device which holds cylinder plugs, cylinders, housings, and/or cores to facilitate the installation of tumblers, springs and/or spring covers

hole change (wheel)

n. a perforated tumbler that may have its combination set by placement of a fly relative to, or in, one of the perforations

hollow core door

n. a non-metal door with structural reinforcement creating air pockets between the two faces

hollow driver

n. a top pin hollowed out on one end to receive the spring, typically used in cylinders with extremely limited clearance in the pin chambers

hollow metal door

n. typically a door made of sheet metal on all surfaces and lightly reinforced to make it rigid

hook

n. a vertical surface at the top of a cut angle that prevents smooth insertion or withdrawal of a key

hook bolt

n. a lock bolt shaped in the general outline of a hook. Normally used on sliding doors or where spreading of the frame and door is a possible attack.

hook pick

n. a pick with a tip that curves upward by 45º or more toward perpendicular to the blade

hook ward

n. a ward that has an offset requiring an 'L' shaped cut in the key

horizontal exit

n. an exit to the outside or an area of refuge on the same or nearly the same level

horizontal group master key

n. the two pin master key for all combinations listed in all blocks in a line across the page in the standard progression format

horizontal locking

n. the locking mechanism associated with vehicle doors with horizontal linkage

horn

n. in a non-cylinder lock, the housing which surrounds the nose and extends through the door or drawer

horn plate

n. the cover of a lever tumbler lock case to which the horn is attached

hospital hinge

n. a hinge with a large chamfer at each end of the knuckle

hotel cylinder

n. a cylinder which can function to prevent the operation of all keys except emergency, display and some shut out keys. It may also contain an indicator.

housekeeper's key

n. a selective master key in a hotel master key system which may operate all guest and linen rooms and other housekeeping areas

housing

n. that part of a locking device which is designed to hold a core

HP

abb. hardplate

hub

n. 1. a lock component, which redirects rotational motion from a spindle or shaft to linear movement of a latch or bolt, 2. (key change), the part of a combination wheel that the change key engages to permit the combination to be changed

hybrid key

n. a key that can operate locks using two or more different technologies in one device, e.g. mechanical/electronic, mechanical/magnetic, etc.

hybrid locking system

n. a locking system which derives its security from two or more different technologies operated by the same key in one device, e.g. mechanical/electronic, mechanical/magnetic, etc.

Source: Lock Industry Standards and Training (LIST) Council