The A-to-Z of Lighting, explained.

Our Lighting Specialists have collated their knowledge to help explain some familar words and phrases used most often to descrbe lighting in Australia and New Zealand.

If you're unclear on any subject, we'd love to assist - please reach out to us.




AC – 'Alternating Current', an electric current that periodically reverses direction.

Aluminium – A silvery-white metal, renowned for its light-weight application, low density and ability to resist corosion

Anodised Aluminium – Aluminium Anodising is accomplished by immersing the aluminum into an acid electrolyte bath and passing an electric current through the material to produce a decorative, durable, corrosion-resistant and/or anodic oxide finish. This aluminum oxide is not applied to the surface like paint or plating, but is fully integrated with the underlying aluminum substrate, so it cannot chip or peel. 




Bayonet Cap – A type of lamp base that requires a ‘push and twist’ action to secure into the lampholder. Also known as BC and B22.

Beam Angle – The angle (expressed in degrees) showing the direction light is distributed from a light source. The wider the beam angle, the more light is spread out. The narrower the beam, the more intense the light is. 

Bollard – A vertical post light that sits above ground, often used in residential gardens to lights paths or gardens. 

Brass – A bright, gold-like metal. 

Bulkhead – A lower portion of the ceiling generally constructed to conceal utility services. 



Ceiling Canopy – A decorative plate that attaches to the ceiling to cover the cables of a pendant. Also known as cup. 

Ceiling Height – The most important factor in lighting. It is the distance between the flat surface of the floor to the flat surface of the ceiling.

Coastal Rating – An indicator of how well a light fitting can withstand coastal weather conditions.

Colour Temperature – The colour of light measured in kelvin. Common terms included ‘warm white’ and ‘cool white’.

Cool White – A high colour temperature where the colour of light is bluish white. Also known as daylight.

Copper – A metal with a reddish-orange colour. Also known as rose gold.

CRI – Acronym for Colour Rendering Index. A measure of how well light perceives colours as seen in daylight.

CTC – Acronym for Close To Ceiling.

Cut-out – The minimum hole size that needs to be cut into a surface to recess a light.




DC – Acronym for Direct Current, which is an electric current that flows in one direction. 

Diameter – The measurement from one edge of a circle to the opposite edge, that passes through the centre point. 

Dimmable – Ability to have the level of light decrease in brightness. 

Dedicated– A fitting where the light source, generally an LED chip, is an integral part of the fitting. 

Diffuser – Any material that diffuses and softens light. 

DIY – Acronym for Do It Yourself. In relation to lighting it means a fitting doesn’t require an electrician to install. 

Downlight (Recessed) – A type of light recessed into the ceiling that directs light downwards. 

Downlight (Surface Mount) – A type of light, often cylindrical in shape, mounted to the ceiling surface that directs light downwards. The perfect solution for lower ceiling heights. 

Driver – A small device that controls the voltage and current supplied to a lamp. A driver can be built-in to a light fitting or remote (separate) to a fitting. It can control an individual light or multiple lights.




Edison Screw – A type of lamp base that you twist around and screw into a lamp holder. Also known as ES and E27. 

Extension – A term of measurement indicating the distance outwards. Also known as depth or projection. 

Extension Rod – An extra length of suspension to increase the drop on a pendant.




Festoon Lighting – Also known as party lights, which are multiple light bulbs hanging on a garland. 

Flood Light – A high intensity light used to illuminate large areas. 

Floor Lamp – A large lamp designed to stand on the floor. 

Fluorescent Lamp – A type of lamp where a phosphor coating inside a glass tube creates a glow when exposed to UV radiation. Cheaper to run than halogen lamps or incandescent lamps.




G9 Bulb – A small light bulb with two connector pins that resemble the shape of a 9. 

Garden Spike – A type of outdoor light with a spike on the bottom that can stick into soft surfaces such as dirt or grass. 

GLS Bulb – Acronym for General Lighting Service, which is the most common type of light bulb, resembling a pear-like shape. 

GU10 Bulb – A mains voltage reflector light bulb that concentrates the beam of light downward. Generally with 2 short, square-like pin connectors that require a ‘push and twist’ action to install. Similar to MR16 bulb.




Halogen Lamp – A type of incandescent lamp with the addition of a small amount of halogen gas in order to reduce heat and increase lamp life.




Incandescent Lamp – A type of lamp where light is created by passing an electric current through a filament (or metal wire) to heat it up, which then becomes visible light. Also known as carbon filament. 

Inground Light – A light fitting recessed into the ground. 

IP Rating – Acronym for Ingress Protection Rating which identifies the level at which a light fitting is protected against both dust and moisture.




Kelvin – A scale used to measure colour temperature.




LED – Acronym for Light Emitting Diodes, which emit light. 

Light Bulb – A source of light encased in glass. Bulb bases include edison screw, bayonet cap, small edison screw and small bayonet cap. 

Low Voltage – A lower, safer voltage supply usually in 12v or 24v. 

Lumens (lms)– The measure of how bright a light source is. 

Luminous Flux – Also known as lux, is the measure of how bright a light source is perceived.




MR16 Bulb –A low voltage light bulb with a ‘multifaceted reflector’ to concentrate the beam of light downward. Generally with a 2 straight needle-like pin connector. Similar to a GU10 bulb.




Non-dimmable – The brightness of light is unable to be decreased.




Path Light – A type of light fitting that illuminates a pathway. Can be recessed into the path and shine light upward, or sit on the surface and shine light downward onto the path. See also Bollard. 

Pendant - A light suspended from the ceiling. It may be suspended by a chain, cord or rod.




Raked Ceiling – A ceiling on an incline. 

Retrofit – A light fitting where the bulb can be replaced and/or upgraded.




Sensor – A device attached to a light fitting used to detect changes in the environment and trigger the light. 

Shade (Light Shade) – A fixture that covers the light bulb on a lamp or pendant to diffuse the light it emits. Generally in a cylindrical or conical shape. 

Small Bayonet Cap – Same as Bayonet Cap but base size is smaller in diameter. Also known as SBC and B15. 

Small Edison Screw – Same as Edison Screw but base size is smaller in diameter. Also known as SES and E14. 

Spotlight – A type of light producing a narrow, intense beam of light. 

SS304 – The most common form of stainless steel that can withstand corrosion from most oxidizing acids, but not from coastal environments. 

SS316 – Marine Grade Stainless Steel that is able to resist the corrosive effects of salt in seawater. 

Stainless Steel – A metal similar to Aluminium but with increased corrosion resistance. 

Step Light – A recessed or surface mounted wall light that directs light downward onto a step.

Suspension – A piece of chain, cord or rod that supports the shade and lamp holder of a pendant.




Table Lamp – A small lamp designed to sit on a table.

Transformer – A small device that changes the voltage and current supplied to a lamp. It generally lowers the voltage to increase safety.




UV – Acronym for Ultra Violet, which is a form of radiation with wavelengths shorter than visible light.




Voltage - A measurement of the pressure of electricity going through a wire.




Wall Light – A light fitting amount to the wall, with the potential to offer direct and indirect light. 

Warm White – A low colour temperature where the colour of light is yellowish or red. 

Wattage – The electrical power of a lamp, expressed in watts.



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