The first time fashion got anywhere near an official United Nations climate conference like the one just held in Glasgow was in 2009. That was COP15 (COP stands for “conference of the parties”), and it was held in Copenhagen. I write “near” a COP because back then fashion was not considered central to the climate conversation. It wasn’t, somehow, serious enough.

Fashion was so marginalized, in fact, that in order to talk about its role in creating, and fighting, climate change, it had to hold its own conference. And so the Copenhagen Fashion Summit, which focuses on sustainability, was born.

It took more than a decade, but things have changed. There has been a lot of talk this year about financial bigwigs finally coming to the COP table, but this is the first year that fashion had a meaningful, extended presence. As Stella McCartney, who created a special “Future of Fashion” materials exhibition at the Kelvingrove Art Gallery said, after almost two decades of pushing fashion to acknowledge its effect on the environment, she was a “COP virgin” no longer.

Here’s what else stuck with me from COP26.

1. There was plenty of official action.

Smack in the middle of the Blue Zone (the official delegate area — that is, the one where world leaders spoke), there was an installation by a fashion collective called Generation of Waste made to mimic a bar chart of the various stages of textile waste, from design through raw materials, garment production and so on.

The United Nations Environment Program released a new version of the fashion charter initially created in 2018, now with 130 signatory companies, including, for the first time, LVMH, and with stronger commitments to halve carbon emissions by 2030 (and reach net zero by 2050).

On the fringe, Federico Marchetti, the former Yoox Net a Porter chairman, unveiled a digital ID created by the fashion task force of Prince Charles’s Sustainable Markets Initiative: a scannable garment tag that acts like a DNA trace for a product’s manufacturing history, using blockchain technology.

And Textile Exchange, an NGO that sounds like a fabric trading post but actually focuses on creating global standards in fashion, presented a trade policy request to national governments supported by 50 brands. That is an unsexy term for a plea to create tariff and import-export structures that incentivize companies to use “environmentally preferred materials” rather than, say, polyester. Which is, by the way, the most used material in the entire fashion industry.

2. A fake fact was finally abandoned.

No one uttered the now discredited but formerly very popular “fashion is the second most polluting industry on the planet” fake stat. Everyone has finally agreed it’s one of the worst, and that’s plenty bad enough.

3. “Degrowth” is the word of the moment.

Degrowth: meaning to make less product. Meaning the action taken in response to the fact that in the first 15 years of this century, clothing production doubled in volume, but the number of times a garment was worn before being thrown away decreased 36 percent. For a long time the response to this kind of data was to urge consumers to “buy less!” and “wear longer!” Now it seems that brands have owned up to their role in the problem.

That said, it’s hard to imagine Bernard Arnault of LVMH or Ralph Lauren standing up at their annual shareholders meeting and announcing that their strategy for 2022 is “degrowth.” (It almost sounds like a potential “Saturday Night Live” skit.) Except that Halide Alagöz, the chief sustainability officer of Ralph Lauren, revealed during a New York Times Climate Hub panel that the brand had secretly been trying it out.

Yup: Ralph Lauren has been practicing degrowth. Not that they call it that, exactly.

The company calls it “financial growth through degrowth of resources,” according to Ms. Alagöz. Which is a terrible name for an interesting initiative, but Lauren is working on it. What it discovered was that it could decouple production from profits, so that even as the company made less stuff, it was able to make money — largely by maximizing its understanding of sell-through. It ended up with less wasted product that had to be downstreamed to outlet stores.

“We have seen our financials getting better although we produce less units compared to five years ago,” Ms. Alagöz said.

4. Resale becomes reuse.

Designers are also getting creative when it comes to product that exists in the world. One of my favorite points came from William McDonough, an author of “Cradle to Cradle,” a sort of founding manifesto on the circular economy, who pointed out that we should think of garments as source materials that can be re-sourced for second and third use.

This is exactly what the British designer Priya Ahluwalia was thinking when she teamed up with Microsoft to create a platform called Circulate, which allows consumers to send their own used clothes to her company. If the clothes are in acceptable condition, they will get remade and incorporated into her next collection, and the donor will get “reward points” toward a new purchase with the brand. It’s a sourcing hack Ms. Ahluwalia said has opened up a whole new channel for fabric and ideas for her.

5. But watch out for “regenerative.”

It’s a growing buzzword in fashion, thanks to regenerative agriculture, a farming technique that helps to restore soil health and nutrients. One of the less discussed aspects of fashion is just how intertwined it is with agriculture — many brands are now investing in supporting regenerative farming — but the word has jumped its tracks and filtered up to companies that boast about a “regenerative strategy” and “regenerative tactics,” which seems to mean … well, it’s not clear what it means. But it sounds good, right?

This is the sort of fuzzy language that can lead to charges of greenwashing, which is why Textile Exchange is working on a specific definition, out next year.

Honestly, they could expand the definition to encompass a whole lexicon of fashion so everyone would be using the same language. For example, another word I bet we will hear more of comes courtesy of a McKinsey report: “nearshoring,” which is to say using suppliers that are not necessarily in your country but are not halfway around the world. After all, according to a presentation by the British brand Bamford, the average merino wool sweater journeys 18,000 miles during its production cycle, from raw material to factory to atelier to shop.

A project for COP27, perhaps.