carbon offset

noun

: an action or activity (such as the planting of trees or carbon sequestration) that compensates for the emission of carbon dioxide or other greenhouse gases to the atmosphere

A carbon offset occurs when an individual company or organization directly or indirectly (by funding projects in other locations) removes greenhouse gases from the atmosphere or prevents a certain quantity of greenhouse gases from being released.

—Tyson Miller, Publishers Weekly, 10 Mar. 2008

also : a quantifiable amount of such an activity that may be bought, sold, or traded especially as part of a system to reduce pollutants in the atmosphere

Purchase carbon offsets. For every pound of carbon dioxide your home releases, you can fund an environment-friendly endeavor that reduces the amount of greenhouse gases released into the air.

—Suze Orman, O: The Oprah Magazine, Fall 2007

When you purchase carbon offsets, you are funding a project that reduces greenhouse-gas emissions elsewhere by, for example, increasing energy efficiency, developing renewable energy, restoring forests, or sequestering carbon in soil.

—Al Gore, An Inconvenient Truth, 2006

Word History

First Known Use

1990, in the meaning defined above

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