Interesting piece by Ben Zimmer on the OUP Blog. I give the first two paragraphs:
When carbon-neutral was named The New Oxford American Dictionary’s Word of the Year for 2006, the choice highlighted how recent efforts to combat climate change have brought forth a whole new class of carbon compounds (the lexical kind of compounds, not the chemical kind!). To be carbon-neutral, you can use a carbon calculator to estimate your household’s carbon footprint. Then you can seek to reduce your own carbon emissions, or you can purchase carbon offsets or carbon credits. Countries can institute carbon taxes, while eco-conscious companies can engage in carbon trading on the carbon market. And maybe someday, if we’re all low-carbon or even zero-carbon, we can live in a post-carbon world.
Putting aside the politics of the global warming debate, lexicographers are particularly interested in how the usage of the word carbon has been expanding in recent years. Not everyone is happy about the carbon boom. Salon’s advice columnist Cary Tennis recently fielded a letter from “Bothered by Bad Buzzwords,” who complained that carbon-neutral and related terms misuse the word carbon. “What I don’t understand is why no one is calling the concept correctly,” the letter-writer grumbled. “Carbon is not carbon dioxide! One is a black solid. One is an odorless, colorless gas. Couldn’t they call it CO2 neutral?”