Even if you’ve committed to ensuring your wardrobe is as eco-friendly as possible, navigating the world of sustainability can be overwhelming, with new buzzwords and scientific jargon popping up all the time. But what do these terms actually mean, and why does it matter?

Being an informed customer means you can avoid greenwashing and ensure that brands you choose are actually taking the action needed to help save our planet and support the people making our clothes. Thankfully, there are plenty of resources out there to guide you, including The Sustainable Fashion Glossary, created by Condé Nast in partnership with the London College of Fashion’s Centre for Sustainable Fashion (CSF). “It is vital that we have clarity and understanding in fashion’s language to talk about the connected environmental, cultural and health crises of our times,” Professor Dilys Williams, director of the Centre for Sustainable Fashion, tells Vogue. “What we [wear] should reflect what we stand up for and this glossary can help in making decisions about what awe-inspiring fashion really consists of.” 

Want to know what transparency actually means, or the difference between biodegradable and compostable? Don’t worry, we’ve got you covered — here are the essential terms you need to know for Earth Day (22 April) and beyond. 

Carbon offsetting 

Fashion needs to cut down its CO2 emissions and fast, with the industry responsible for between four to 10 per cent of global greenhouse gas emissions every year. That’s why an increasing number of brands have started carbon offsetting: investing in projects that are focused on reducing emissions, such as forest restoration. However, carbon offsetting (which often takes place in developing countries) is by no means a perfect solution, and shouldn’t distract from the real need for companies to tackle their own carbon footprint directly. 


Microplastics are tiny plastic particles that are increasingly polluting our planet, with synthetic clothing being a major culprit. In fact, estimates suggest that as much as 20 to 35 per cent of microplastics being released into our oceans come from textiles, posing a huge threat to the marine life that ingests them. Luckily, there are everyday things we can do to help tackle the issue, including avoiding synthetics where possible and using a microplastics filter, such as a Guppyfriend bag or a Cora Ball, when you do your laundry. 

Natural fibres

Natural fibres — which come from plants or animals — are generally considered more sustainable than synthetics (which are derived from fossil fuels), and include cotton, linen and wool. But natural fibres still have varying degrees of impact, with organic cotton less harmful to the environment than conventional cotton and leather having a larger carbon footprint in comparison to polyester, for instance. While natural fibres themselves are biodegradable, the chemicals used to treat them in the manufacturing process may not be (see below). 

Biodegradable materials

You’ve probably seen an increasing number of products branded as biodegradable, whether that’s the garments themselves or the packaging they come in. And while biodegradable materials do break down naturally via microorganisms such as bacteria and fungi, there are no guarantees: conditions such as temperature and nutrients will affect biodegradability, as will dyes and washes used to treat materials. It’s also worth noting that biodegradable is different to compostable, with the latter usually requiring a managed process. 


As customers become increasingly conscious about their purchases, greenwashing — when brands make false or misleading claims about their environmental policies — is also on the rise. This includes descriptions of products as being sustainable, just because they contain a small amount of recycled content. To avoid greenwashing, look for facts and figures that back up a brand’s claims, rather than taking them at face value. 


As brands become more conscious of the impact of raw materials, upcycling has become a growing trend in the industry, with the likes of Balenciaga, Miu Miu and Marni all making use of pre-existing materials in recent seasons. Upcycling means turning discarded materials and products into items that have a higher value, whereas recycling usually means turning a discarded product into a like-for-like item. 


Biodiversity is the variability of species on our planet and is crucially important — considering how connected our ecosystems are. A shocking one million species are now at risk of extinction, with the rate of biodiversity loss estimated to be happening at 1,000 times the natural rate. Considering the vast majority of materials used in fashion come from nature (whether that’s cotton grown in fields or viscose from trees), the industry is slowly waking up to its role in this, with both Kering and LVMH announcing new initiatives aimed at restoring biodiversity this year. 


With an astonishing 100bn garments produced globally each year, overconsumption is a real problem. Put simply, we are getting through more garments than we actually need and making more clothes than our planet can take. In fact, it’s estimated that the number of times a garment is worn has decreased by 36 per cent within the past two decades, often ending up in landfill. That’s why the mantra ‘buy less and buy better’ is more important than ever. 


Greater transparency from brands is required for us to know if they are following through on their sustainability commitments. This means companies disclosing information across entire supply chains, including social and environmental policies. While campaign group Fashion Revolution produces an annual Fashion Transparency Index, it’s important to remember that brands that are more transparent aren’t necessarily more sustainable. 

Ethical trade

While the words ‘sustainable’ and ‘ethical’ are sometimes used interchangeably, ethical trade refers specifically to the way the people across the fashion supply chain are treated — from those growing the raw materials to those working directly for a fashion company. For a brand to be operating ethically, workers’ rights — such as maximum working hours, health and safety, freedom of association and fair wages — must be adhered to.