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This glossary is brought to you courtesy of  Earth911. This glossary will be updated periodically.

Definitions or information about substances or program activities not included herein may be found in EPA’s
Terms Of Environment.





Air Pollution— How the air we breathe is contaminated by man-made or natural particles, liquids or gases. This could include everything from factory exhaust to emissions from our cars.


Aluminum— A highly-recyclable metal that also has high resale value when recycled. It is commonly found in soda cans, and is a member of The Big Five. Aluminum is a lightweight, silver-white, metallic element that makes up approximately 7 percent of the Earth’s crust. Aluminum is mined in the form of bauxite ore where it exists primarily in combination with oxygen as alumina. Aluminum is used in a variety of ways, but perhaps most familiarly in the manufacture of soft drink cans.



Big Five— The five most commonly Curbside recycling programs will incorporate most (if not all) of these materials.


Biodegradable— Description for anything that is able to be broken down by living organisms such as bacteria or fungi. Some biodegradable materials can serve as the ingredients for compost. Items that take a long time to biodegrade will pile up in landfills.


Biofuel— Type of renewable resource that is produced from biomass, a recently living element such as animals, plantlife or wood. It can provide energy from unexpected sources, such as the gas from landfills. One of the biggest potential forms of biofuel is biodiesel, which lessens cars’ dependence on gasoline.


Biomass— All of the living material in a given area; often refers to vegetation.


Buyback Center— Facility where individuals or groups bring recyclables in return for payment.  





Carbon Footprint— The tangible impact someone’s activities will have on the environment, measured in units of carbon dioxide produced. To reduce a carbon footprint is beneficial to the environment, which is why there are calculators to measure and reduce these footprints.


Carbon Neutral— An activity or event that has successfully balanced the carbon footprint with carbon offsets, thereby negating the environmental impact. Businesses have been known to attempt carbon neutrality on certain projects.


Carbon Offset — One way to compensate for a carbon footprint, essentially by investing money in a project that will benefit the environment and cancel out the emission of carbon dioxide from a certain activity. The most common form of carbon offset is planting trees because they will absorb carbon dioxide.


Carpool— Form of transportation by which two or more people travel to the same destination together to reduce the emissions of traveling. Many cities have separate lanes set up for carpoolers so they can avoid traffic jams.


Cathode Ray Tube (CRT) – Can be classified as TV sets, computer monitors and medical/technical equipment.  CRT's can no longer be disposed of in landfills and are categorized as Universal Waste.  CRT's contain lead and other hazardous substances used as shielding from dangerous electromagnetic emissions. 




Climate Change— Term for a significant change from one climatic condition to another, such as temperature of the Earth over time. In some cases, it has been used synonymously with the term “global warming;” scientists tend to use the term in the wider sense to also include natural changes in climate.


Clean Air Act— Law originally passed in 1970 (amended in 1990) to help clean up air pollution. It has resulted in the implementation of tougher policies designed to reduce emissions of chemicals from businesses and automobiles into the air.


Clean Energy Act— Law originally passed in 2007 to reduce the dependency on non-renewable energy sources such as coal and oil. It requires the investment in energy technology including solar and wind power, while reducing the United States’ dependence on foreign oil for energy.


Clean Water Act— Law originally passed in 1972 (amended many times since) to help clean up water pollution. It has set wastewater standards for businesses and boats, as well as water quality standards for any potential water contaminants, and funded the construction of sewage treatment plants to reuse wastewater.


Close the Loop— Term for recycling process. These products have the same stability of new products, and are often referenced as recycled content on the packaging. It refers to the point when a consumer buys a recycled product after it has been put into a recycling program and reprocessed into a new item.


Commercial WasteAll solid waste emanating from business establishments such as stores, markets, office buildings, restaurants, shopping centers and theaters.  


Compact Fluorescent Lightbulb— Commonly referred to as a CFL, these bulbs are spiraled in appearance and can be used in place of an incandescent bulb. CFLs are more energy efficient and can last much longer than incandescents. These bulbs also contain traces of recycled instead of trashed.


Compost— Process by which food scraps from a home or business are disposed of naturally to produce toxin-free and nutrient-rich fertilizer for gardening and other uses. Compost reduces your solid waste output and can save money on your garbage bill. Composting is Nature’s way of recycling. Compost is a mixture that consists largely of decayed organic matter and is used for fertilizing and conditioning land. EPA DEFINITION: The relatively stable humus material that is produced from a composting process in which bacteria in soil mixed with garbage and degradable trash break down the mixture into organic fertilizer.


Conservation – Conservation is the wise use of natural resources (nutrients, minerals, water, plants, animals, etc.). Planned action or non-action to preserve or protect living and non-living resources.


Construction & Demolition (C&D) – Building materials and solid waste from construction, deconstruction, remodeling, repair, cleanup or demolition operations, in some cases these materials can be reused.  


Covered Load – A load that has been tied down or covered to prevent waste from falling, blowing, or spilling out of the transport vehicle.  



Deforestation— Process by which forested areas are cut down, usually to make room for agricultural development or settlement. The reduction of trees prevents the consumption of carbon dioxide and pollutants from the air, and also affects the condition of soil, groundwater and climate in the area.


Drought— An extended period of time with a reduced level of water, usually brought on by the absence of rainfall. Drought has been linked to issues such as deforestation and global warming, as the natural state of these affected ecosystems has been altered. It has a significant impact on an area’s water supply.



Ecological Sustainability –  Maintenance of ecosystem components and functions for future generations.


Ecosystem – A community of animals and plants living together with it's environment.


Electronic Waste— Commonly referred to as recycled. Many states have outlawed throwing e-waste in the trash because it contains hazardous materials.


Energy Audit— Similar to a carbon footprint, this is a way to determine how much energy certain activities are expending in order to figure out ways to reduce this. Energy audits can often be done with the help of a utility company that measures a building’s energy use from month to month.


ENERGY STAR— Rating system that showcases the electronic products and lighting. It was developed by the EPA and the U.S. Department of Energy in 1992 and is also a rating system for buildings in the United States.


Environment – The sum of all external conditions affecting the life, development and survival of an organism.


Environmental Protection Agency — Commonly referred to as the EPA, a government agency founded in 1970 that protects human health and the environment through programs for consumers and businesses.



Food Waste— Uneaten food and food preparation wastes from residences and commercial establishments.


Fossil Fuel— The remains of plant and animal life that can be used to provide energy by combustion, such as coal, oil or natural gas. It is a non-renewable resource, and the burning of fossil fuels results in carbon dioxide emissions.


Fuel Economy— Number that corresponds to the amount of miles that a vehicle can travel on a gallon of gasoline, referred to as miles per gallon (MPG). The higher the MPG of a vehicle, the more eco-friendly it is likely to become, and the less it is dependent on non-renewable resources.



Glass— Glass is a hard, brittle, generally transparent or translucent material typically formed from the rapid cooling of liquefied minerals. Most commercial glass is made from a molten mixture of soda ash, sand, and lime. A commonly-recycled material in glass bottles are easily recycled, other forms of glass that are treated (e.g. Pyrex) will not be accepted by many programs.


Global Warming— Term used to describe an increase in the near surface temperature of the Earth. It is most often used to refer to the warming predicted to occur as a result of increased emissions of greenhouse gases. Scientists generally agree that the Earth’s surface has warmed by about 1 degree Fahrenheit in the past 140 years.


GrasscyclingSource reduction activity in which grass clippings are left on the lawn after mowing.


Gray Water— Any energy, and cuts down on the use of fresh water.


Green Building— Process of constructing a new building while taking into account U.S. Green Building Council with levels of certification for qualified buildings.


Greenhouse Effect – The effect produced as greenhouse gases allow incoming solar radiation to pass through the Earth’s atmosphere, but prevent most of the outgoing infrared radiation from the surface and lower atmosphere from escaping into outer space. This process occurs naturally and has kept the Earth’s temperature about 60 degrees Fahrenheit warmer than it would otherwise be. Current life on Earth could not be sustained without the natural greenhouse effect.


Greenhouse Gas— Any gas that absorbs infra-red radiation in the atmosphere. Greenhouse gases include water vapor, carbon dioxide (CO2) and methane (CH4), and reduction of their emissions also reduces a carbon footprint.


Grid Electricity— Electricity that is transmitted to a building from the public electricity network. Buildings that don’t rely on alternative forms of energy tap into the grid for electricity. Those that don’t tap into this source are referred to as “off the grid.”


Groundwater— Water that is contained within the ground of the Earth, such as in soil moisture or dew from plants. It makes up about 20 percent of the world’s fresh water supply, and is highly subject to pollution.



Hard to Handle Waste— Items whose dimensions exceed four feet in either width, length or height and which require special handling.


Hauler— Garbage collection company that offers complete refuse removal service; many will also collect recyclables and greenwaste.


Hazardous Waste— A product in a home (household hazardous waste) or business that is ignitable, corrosive, reactive or toxic (e.g. used motor oil, oil-based paint, auto batteries, gasoline, pesticides, etc). These products are damaging to the environment if disposed of improperly. Many of these products have eco-friendly alternatives.


Hybrid Electric Vehicle— Commonly referred to as a hybrid, this is a form of car that combines both a traditional gasoline-powered engine with a rechargeable energy storage system to achieve better fuel economy. These vehicles are able to charge while in motion so they do not need to be plugged in, and result in lower emissions.



Kyoto Protocol— An international agreement between 137 (and growing) developed countries to work toward reducing greenhouse gas emissions that cause climate change. It was originally passed in 1997 in Kyoto, Japan and is set to expire in 2012; the United States has signed but not ratified the agreement, meaning it is non-binding in the U.S.





Liquid Waste - Residential and commercial septic tank waste, chemical toilet waste, grease trap waste and car wash clarifier pumpings.


Litter - Waste that is improperly disposed of on the street, sidewalk, lakes and other bodies of water, and in the general environment.


Low-Flow— Description for water-using products that require less water per use. The two most common examples are low-flow showers and low-flow toilets.



Material Recovery Facility (MRF) - A facility that processes collected mixed recyclables into new products available for market.


Medical Waste - Infectious agents such as human pathological wastes, human blood and blood products, used or unused sharps (syringes, needles and blades), certain animal waste, and certain isolation waste.


Mercury— Metal with the atomic symbol Hg, commonly found in thermometers, electronics switches and other devices. It is toxic to humans if inhaled or ingested, and (similar to mercury are improperly disposed of.


Municipal Solid Waste— Term for solid waste generated by households, commercial establishments, industrial offices or lunchrooms not regulated as a residual or hazardous waste. It constitutes anything thrown in a garbage can that will end up in a landfill, regardless of whether it is eligible for recycling or reuse. This does not include source-separated recyclables.



Non-Renewable Resource— A resource that is not capable of being naturally restored or replenished and is thus in limited supply. It is most commonly used to describe energy sources such as coal and oil. The use of these materials and energy sources leads to depletion of the Earth’s reserves and are characterized as such as they do not renew in human relevant periods (They are not being replenished or formed at any significant rate on a human time scale).



Organic Product— Way of producing items that is more beneficial to the environment, since it reduces the use of harmful chemicals like pesticides. It is generally thought of as a healthier alternative as it is less treated with chemicals, and is most commonly associated with food products. Organic can also refer to molecules made up of two ore more atoms of carbon, generally pertains to compounds formed by living organisms.



Packaging— The wrapping material around a consumer item that serves to contain, identify, describe, protect, display, promote and otherwise make the product marketable and keep it clean. Packagingis often difficult to biodegrade, meaning that a reduction in the amount of packaging used is better for the environment.


Paper— Most common material in most Paper comes in many forms (office paper, mixed paper, cardboard) and all can be reduced, reused and recycled. Unlike other materials, paper can’t be recycled infinitely; it loses fibers every time.

PET - Polyethylene terepthalate. A type of plastic used to make soft drink bottles and other kinds of food containers. PET is also used to make fabric.


Plastic— A material made from petroleum capable of being molded, extruded, or cast into various shapes. There are many different kinds of plastic made from different combinations of compounds. This material is a member of The Big Five that is often included in recycle it.


Pollution – Contamination of air, soil, or water with harmful substances.


Post-Consumer – A term used to describe material that is being reused/recycled after it has been in the consumer’s hands (e.g., a newspaper going back to the paper mill to be recycled into new recycled content paper products). Material or product used by the consumer for its original purpose and then discarded.


Pre-Consumer – A term used to describe material that is being reused/recycled before it ever goes to market (e.g. paper scraps off of a paper mill floor going back into the next batch of paper). Waste material generated during the manufacturing process.


Public Transportation— Any form of transportation offered by a city or town to reduce the congestion of streets and the pollution of air. Whether it’s airplanes, buses, ferries or trains, these transports often utilize renewable resources to reduce the environmental impact of traveling on them. They also serve as an alternative to carpooling.



Recyclable – A term used to designate that a product or its package can be recycled. This term may be misleading as there may not be a recycling program that takes the identified material in the consumer’s area.


Recycle— Process by which a material is diverted from landfills and instead reprocessed into a new product. It is the third R in the Three R’s process; products which are recyclable are marked with the recycle symbol.


Recycle Symbol— A chasing arrow diagram found on products that can be recycled content. On plastics, it is used along with a numbering system (1-7) to help designate plastic resins used in the product.The three arrows on the symbol represent different components of the recycling process. The top arrow represents the collection of recyclable materials (e.g. an aluminum can, a piece of white office paper, a plastic #2 milk jug) for processing. The collection can be from a curbside collection or a drop-off site. The second arrow (bottom right) represents the recyclables being processed into recycled products (e.g. a new aluminum can from an old aluminum can, notebook paper from white office paper, a park bench from recycled plastic milk jugs). The third arrow on the bottom left is the most important arrow. This one represents when the consumer actually buys a product with recycled content. This is the most important step as it closes the recycling loop. Without this last step, we are pretty much just sorting our garbage.


Recycled Content— Amount of recovered material used to manufacture a new product, usually expressed as a percentage (e.g., 30 percent post-consumer content). Purchasing recycled content is how you close the loop.




Recycling Center – A place where recyclables are collected and/or processed (such as separation and baling) in preparation for market.


Reduce— Process by which activities and waste can be altered to conserve resources. Reduction can also involve a decrease in water use, and is the first R in the Three R’s process.


Renewable Energy Credit— Commonly referred to as a green tag and similar to carbon offsets, this is the purchase of a 1 megawatt-hour (MWh) unit renewable energy. You can purchase these units to compensate for the use of non-renewable energy.


Renewable Resource— A resource that is capable of being naturally restored or replenished, such as a tree. It is most commonly used to describe alternative forms of energy such as solar and wind power, which can be continually reproduced using natural resources.


Residential Waste - Typically consists of domestic garbage and rubbish, including food and beverage containers, paper, food wastes, wood and green wastes.


Reuse— Process by which products are given a second (or third) life prior to disposal. Reuse is the second R in the Three R’s process, and allows for the reduction of new products.



Sanitary Landfill – A landfill that has been designed and engineered to accept municipal waste while ensuring minimal negative impact upon the environment.


Solar Panel— Device that is able to harness the power of the sun and turn this energy into electricity for a building or home. Because these buildings are powered by an alternative form of energy, they are often referred to as “off the grid” since they don’t consume power from the utility company’s electricity grid.


Source Reduction— The act of reducing the amount and/or toxicity of an item before it is ever generated, such as buying an item with less packagingor using a non-toxic alternative to clean with.


Steel— This is the most commonly recycled material in North America and a member of The Big Five. It can be included in recycled into new steel.


Sustainability— Term for a system that has potential longevity in our current ecosystem, and is usually applied to the use of renewable vs. non-renewable resources. For a system to be sustainable, it must be able to survive indefinitely, which would imply the use of renewable resources because they are in infinite supply.



Three R’s— This is a group of terms crucial to sustainability: reduce, reuse and recycle. The first step is reducing things like energy use and waste output, then reusing products for a second purpose, and finally recycling them so they are diverted from landfills.


Toxicity— The amount of a poisonous substance that exists in a given material. Toxins can be naturally occurring or man-made, and often are linked to water.



VermicompostingThe process whereby worms feed on slowly decomposing materials (e.g., vegetable scraps) in a controlled environment to produce a nutrient-rich soil amendment.


Virgin Product— Any product that is made with 100 percent new raw materials and containing no recycled content.



Wastewater— Any water that has been used for any business or residential purpose (including any human waste), rainfall that travels down a drain and discharge from factories. Wastewater can be treated in a certified plant and reused for human consumption.


White Goods - Refrigerators, stoves, washers/dryers, water heaters, dishwashers, trash compactors, air conditioners and similar items.  These items can be disposed of through your haulers bulky item pickup program.


Wind Turbine— Device that absorbs energy from wind through a propeller system which is transferred into renewable energy. The most common type of turbine is a windmill, which is pointed toward the wind and rotates when a gust comes.


Wood Waste - Wood scraps, lumber, branches, pallets, or similar woody materials that are suitable for grinding or possible reuse.



Zero Waste*— Zero waste is a philosophy that encourages the redesign of resource life cycles so that all products are reused. Any trash sent to landfills is minimal. The process recommended is one similar to the way that resources are reused in nature.


*Definition taken from Wikipedia