Entries starting with H

A covering for the head, often in the approximate form of a cone, dome or cylinder closed at its top end, and sometimes having a brim and other decoration.

hatch

An opening into, or in search of, a mine.

hatchwork

nounMarine and shipyard

The apparatus around the hatches of a vessel, particularly the cargo hatch

haul road

A road designed for heavy or bulk transfer of materials by haul trucks.

haul truck

An off-road, heavy-duty dump truck specifically engineered for use in high-production mining and exceptionally demanding construction environments.

haulback

A method of surface mining where overburden (the material on top of the coal or ore) is transported from an area and then hauled back after removal of ore or coal.

haulier

A miner who hauls coal from the coalface to the bottom of the shaft.

A type of silage with a high dry-matter content, made from the same grasses or legumes from which hay is made (such as alfalfa, timothy, and others) but not dried as much as hay nor as little as direct-chop/green-chop silage (before being ensiled).

haymaker

nounAgricultural equipment

A person or machine which harvests or prepares tall grass for use as animal fodder.

Hazcam

nounAviation maintenance

Abbreviation of Hazard avoidance camera, a type of engineering camera mounted on the front and rear of certain unmanned space rovers including the Curiosity rover at Mars.

haze

Any substance causing turbidity in beer or wine.

HBM

Initialism of high-bandwidth memory.

HBO

phraseAviation maintenance

Initialism of hand baggage only (fare type).

HBT

Initialism of herringbone twill.

HCL

nounOptics and imaging

Initialism of hue-chroma-luminance.

HCLK

Acronym of high-speed clock.

HCV

nounAutomotive

Initialism of heavy commercial vehicle

HD DVD drive

An optical drive used for reading data from and possibly writing data on an HD DVD.

HDA

nounMetallurgy

Abbreviation of hot-dip aluminization.

HDL

nounElectrical engineering

Initialism of hardware description language.

HDR

Initialism of hard disk recorder or hard drive recorder (“a recording device that records onto a hard disk drive”).

HDSL

nounElectrical engineering

Initialism of high-bit-rate digital subscriber line.

head

nounMachining

The topmost, foremost, or leading part.

head gasket

nounMechanical engineering

The gasket which seals a cylinder head to an engine block in several types of engine, including steam engines and internal combustion engines.

head unit

nounAutomotive

The in-dash control box, excluding the dash-mounted interaction screen.

head-on

adjectiveAutomotive

Of a collision, from the front or in the direction of motion.

head-on collision

nounTransport and logistics

A collision where the front ends of two vehicles (such as ships, trains, cars, planes, etc.) hit each other.

headband

nounIndustrial printing

A thin slip of iron on the tympan of a printing press.

headboard

nounRail equipment

A board on the front of a train, carrying the train's name or that of the service it is on.

headchair

nounRail equipment

Part of a block switch on a railway line that the ends of the moveable rails rest on, and to which the stationary rails are attached.

headcode

nounRail equipment

A code used to distinguish classes of train for the benefit of signalmen, formerly by using white oil lamps (or white discs) placed on brackets on the front of the locomotive. The various lamp positions defined the class of train.

header

A brick that is laid sideways (on its largest face), for example at the top of a wall or within the brickwork, with its smallest side showing (oriented so that that side is wider than it is tall).

headframe

the structure supporting machinery above the entrance to an underground mineshaft.

heading

A gallery, drift, or adit in a mine, particularly one driving through a solid body of coal or ore; also, the end of a drift or gallery; the vein above a drift.

headlight fluid

nounIndustrial supplies, equipment, and componentsslang

A fictional ostensible automotive product, used in jokes, to prank someone into searching for the nonexistent item (a snipe hunt), or to gauge how inept someone is in basic auto mechanics.

headline

nounIndustrial printingdated

The line at the top of a page containing the folio or number of the page.

headliner

nounAutomotive

The interior fabric covering the ceiling-like area inside of a vehicle.

headpiece

nounIndustrial printing

A decorative page heading used at the start of volumes or chapters.

headroom

The ability of a system to reproduce loud sounds free of distortion; dynamic headroom.

headsman

A labourer in a colliery who transports the coal from the workings to the horseway, and who is oftentimes assisted by a younger worker called a foal.

headstick

nounIndustrial printing

A straight piece of furniture placed at the head of a form, between the chase and the type.

heapstead

The elevated framework of wood or iron at bank, to the top of which the pit is continued above the surface, to provide the necessary height to pass the coals over the skreens into the wagons.

heart

verbConstruction

To fill an interior with rubble, as a wall or a breakwater.

heart bond

A bond in which no header stone stretches across the wall, but two headers meet in the middle, and their joint is covered by another stone laid header fashion.

heartbond

A bond in a stone wall in which two headers meet in the middle of a wall and another header covers the joint between them.

hearting

Material used as fill between walls of greater structural integrity, especially in masonry.

heat shield

nounAviation maintenance

A shield designed of a substance that absorbs excessive heat from an outside source by either dissipating, reflecting or simply absorbing the heat.

heather