Anthropogenic - Resulting from or produced by human beings. ‘Anthropogenic climate change’ refers to climate change caused by human activity as opposed to natural causes.

Biomass – (1) a total mass of living (or recently living) organisms in a given environment, (2) plant and/or animal material, for example, processed green waste used as a fuel source.

Biodegradable - Materials capable of being decomposed back into the environment by natural biological processes.

Biodegrade – To degrade naturally as the result of the action of bacteria.

Carbon cycle - The term used to describe the flow of carbon (in various forms, including fossil fuels, living plant tissues and carbon dioxide gas) through the atmosphere, ocean, terrestrial biosphere and lithosphere.

Carbon dioxide (CO2)– Carbon dioxide is a compound. Each molecule is made up of a carbon atom bonded with two oxygen atoms. At room temperature and normal pressure it is a gas. Carbon dioxide occurs naturally in large quantities from natural processes, notably respiration by living organisms. Other natural sources include volcanoes, forest fires and evaporation from seawater. Carbon dioxide emissions from human activity largely come from the combustion of fuels, for example in coal-fired power stations or petrol car engines. Carbon dioxide is one of the major greenhouse gases.

Carbon dioxide equivalent (CO2eq or CO2e) – A standard measure that expresses the amount of global warming impact of greenhouse gases in terms of the amount of carbon dioxide (CO2) that would have the same global warming potential. (Also see Global warming potential). For example, although combusting a litre of petrol in a car produces exhaust that has a range of different greenhouse gases, its greenhouse emissions are expressed as 2.8 kg CO2e per litre.

Climate change - Significant variation in the Earth's global climate or in regional climates over time. Climate change refers to changes in the variability or average state of the atmosphere over time scales ranging from decades to millions of years. In many cases, it is used as a general term. However, there are other terms that differentiate climate change based on various causes. Climate change due to human activity is generally referred to as ‘anthropogenic climate change’ or simply as ‘climate change’, while ‘climate variability’ is used to describe climate change attributable to natural causes.

E-waste - The waste associated with the use and disposal of electronic equipment such as computers, televisions, printers, etc. E-waste can contain a broad range of materials including precious metals (including gold and platinum), toxic heavy metals, metal circuitry, mixed plastics, fire retardants and glass.

Embodied energy – The amount of energy necessary for the fabrication of a specific material or product. When measuring embodied energy, all energy inputs are considered, from raw material extraction, to transport, manufacturing, assembly, transportation, installation and others. Embodied energy as a concept seeks to measure the true energy cost of an item.

Embodied water or virtual water – The amount of water necessary to produce a specific material or product, including food crops. When measuring embodied water, all wwater inputs are considered, from water in agriculture, to processing, manufacturing, assembly, transportation, installation, water used in company administrative offices and others. Like embodied energy, embodied water as a concept seeks to measure the true water cost of an item or commodity. Note that some definitions of embodied or virtual water don’t include natural precipitation in measuring water in agriculture (only counting irrigation) while others include this in their water accounts.

Extended Producer Responsibility (EPR) - EPR is a policy approach in which a producer or manufacturer takes responsibility for the environmental impacts of their products throughout the entire life cycle of the product. Traditionally, the environmental responsibility of producers focused on the environmental impacts of their factories. EPR extends this to also include any impacts of the product in it use and ultimately its disposal.

Global warming - Global warming is the increase in the average temperature of the Earth's near-surface air and oceans in recent decades and its projected continuation. It is believed to be cause by a number of factors including solar variation, volcanic emissions, variations in the earth's orbit and the greenhouse effect.

Global warming potential (GWP) – A measure of how much a unit of a particular greenhouse gas is estimated to contribute to global warming compared with a unit of carbon dioxide over a set period of time. Carbon dioxide is defined as having a GWP of 1, and other greenhouse gases are measured with this as the reference. For example, the GWP of methane 21 times that of carbon dioxide and halofluorocarbon group of chemicals (HFCs), commonly used as refrigerants and propellants, have GWP values ranging from 100 to 3800 times that of carbon dioxide. Given that carbon dioxide is the reference greenhouse gas, standard measures of greenhouse emissions are often quoted as a ‘carbon dioxide equivalent’ weight (CO2e).

Landfill - An area of land that is designated to contain waste. Waste is deposited in layers, then compacted and covered.

Life cycle analysis or life cycle assessment (LCA) – An assessment of the total environmental impacts of a product or service throughout its entire lifespan.

Product Stewardship - The responsible attitude of a manufacturer to ensure that their products have minimal environmental impacts throughout their life. Also see Extended Producer Responsibility, which is similar.

Raw Materials - The basic materials or 'ingredients' used as feedstock for processing into new materials or products. For example, bauxite is the raw material that is processed into aluminium.

Resource Recovery - The collection and therefore "recovery" of products and materials from the waste stream for reuse, recycling, energy generation or composting instead of disposal.

Reuse - Repeated use of a product in its same state with minimal processing. Examples of reuse include the reuse of milk cartons an seedling guards for tree planting or the reuse of shopping bags (preferably biodegradable) as bin liners.

Secondary Raw Materials - Like raw materials, these are materials that are used as feedstock or ingredients to make new products. However, secondary raw materials are collected recyclable materials, which can be used instead of virgin raw materials in manufacturing with little or no change to the manufacturing process. Secondary raw materials, such as scrap metals, can be traded as commodities.

Take-Back Programs - Waste and recycling programs in which unwanted or used goods are returned to their original manufacturer instead of being disposed of. Ideally, the manufacturer then takes responsibility to ensure that these goods are reprocessed, recycled or disposed of in an environmentally sound way.

Virgin Materials - Basic natural materials that are extracted from the ground or harvested and processed into new materials or products. For example, bauxite is the raw material that is processed into aluminium, petroleum for plastics manufacture, iron ore for steel manufacture and wood pulp for paper manufacture.

Waste - Any unwanted by-products of mining, manufacturing, processing, day-to-day living and working and other human activities. Generally, these are the materials for which we have no further use and wish to dispose of.

Waste Avoidance - The management of waste by not creating the waste in the first place.

Waste Hierarchy - The waste hierarchy is a general model that places different approaches to managing waste in an order of priority that reflects their different environmental consequences. The order is: avoid (1), reduce (2), reuse (3), recycle (4), energy recovery (5), and landfill (6). Landfill is the least desirable outcome model. The "3R's" – reduce, reuse & recycle – is a simpler, commonly used version of the waste hierarchy. More complex versions can also be developed and used.

Waste Stream - The collective term for a group of wastes from a common source.