Term Definitions

THIS PAGE IS BEING DEVELOPED. I am taking term definitions out of the footnotes of individual posts and accumulating them here. That will allow terms to be re-used in future posts while retaining one definition. It will also allow them to be perused in one place.

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AB, C, D, E, HPS, T, W, Y.



A decorative moulding (shaped strip of wood) fitted to the outside of a door jamb and lintel or around a window frame. It overlaps the frame and the plasterwork of the wall to improve the finished look of a doorway or window.


British Standard Pipe (BSP)

A thread style applied to some pipes and pipe fittings manufactured/used in the UK.


Capillary Fitting

A type of copper pipe fitting that is soldered to a copper pipe. The fitting is an exact fit to the diameter of pipe it is intended for so that when molten solder is applied to the joint the solder flows between the pipe and the fitting by capillary action. Both metal surfaces must be clean and bright before they are heated. A paste flux is used to prevent oxidation of the copper when heat is applied (usually from a blowtorch).

Clapping Strip

A strip of wood fixed to a door jamb, lintel or window frame to prevent a door or window being pushed beyond the normal closed position. When the door or window is closed it claps against the clapping strip and comes to a halt.

Compression Fitting

A type of pipe fitting using a nut to compress an olive shaped sealing ring onto copper pipe, e.g. Conex | Bänninger. Olives are usually made of brass but some are copper.



Elbow (pipe fitting)

A pipe fitting with a sharp angle like a human elbow in it. The angle is usually a right angle but 135° is available. An elbow is used to make a pipe change direction abruptly unlike a swept bend which gently curves into another direction.


Faucet (in USA) or Tap (in UK)

A hand operated valve with an open end. Adjusting the valve regulates the outflow of fluid from it. These valves are usually connected to a pipe or container.


The platform for the crew in the cab of a locomotive (particularly steam locomotives.)



Hasp and Staple

Hasp and Staple
Hasp (left) and Staple (right)

A device for securing a door with the aid of a padlock. One part is attached to the door and the other part is attached to the door frame (jamb). The hasp loops over the staple and the padlock passes through the staple to secure it.









Padding Board

A wooden board attached to something to make it thicker by padding it out.


A position in which someone holds their body.

Prone or Prostrate

Lying on the floor face down.




Semi-pedestal Wash Basin

A semi-pedestal wash basin is bolted directly to the wall, or a frame within the wall, without a supporting pedestal. The pipework for the taps and waste are covered with a porcelain cover beneath the basin. The height of the cover is roughly half that of a full pedestal, hence semi-pedestal.

Stopcock or Stop Valve

A hand operated valve to allow or prevent water from flowing along a pipe. In particular one is placed inline with a water pipe where it enters a property.


Lying on the floor face up.


Tanalised Timber

Tanalised timber has been treated to prevent wood rot.

Tap (in UK) or Faucet (in USA)

A hand operated valve with an open end. Adjusting the valve regulates the outflow of fluid from it. These valves are usually connected to a pipe or container.

Trap (as used in a waste water pipe)

In a waste water pipe gases (methane & poisonous fumes) can pass from the sewer to the air in a building if there is no vent and a gas barrier (trap) built into the pipe.

A plumbing trap can be as simple as a section of pipe which has water in it. The water traps the gas in the pipe to one side of the water barrier. In practice traps are specially shaped sections of pipe or devices capable of retaining water, held there by gravity. Low pressure gas cannot pass from one side to the other or move the water out of the way. The gas is kept at low atmospheric pressure by venting the gassy section to the air with a vertical pipe.

This method has been used for over 200 years to prevent smelly and explosive sewer gas (methane), at atmospheric pressure, from entering buildings. See this article on the many types available at diydata, and this at Wikipedia.




Wrap Around Board

A board fixed to the hinge side of a door such that it wraps around the door frame (jamb) when the door is closed. The board is intended to prevent the hinge side of a door being forced open after removing or damaging the hinges.



Yagi-Uda antenna (aerial)

A Yagi-Uda antenna is mostly referred to as a Yagi antenna. Mr Yagi and Mr Uda were the Japanese inventors of this style of antenna commonly used for short wave radio and VHF/UHF terrestrial television reception. See the detailed description in Wikipedia.