ex·​ter·​nal·​i·​ty | \ˌek-ˌstər-ˈna-lə-tē \
plural externalities

Definition of externality 

1 : the quality or state of being external or externalized

2 : something that is external

3 : a secondary or unintended consequence pollution and other externalities of manufacturing

Examples of externality in a Sentence

Recent Examples on the Web

But on a macro level, the NBA is an environment largely shaped by externalities, an aggregate sum of hundreds of cases of individual self-interest and their exponents. David Murphy, Philly.com, "How LeBron James' decision may change Sixers' Star Hunt approach | David Murphy," 2 July 2018 Memphis’ average tuition is about $9,700 a year, not including externalities. Bradford Betz, Fox News, "University of Memphis says children, spouses of fallen service members will no longer pay tuition," 29 May 2018 But carbon offsets don’t erase externalities like vehicular congestion or particulate pollution, and various studies have revealed that ride-hailing is actually increasing vehicle-miles traveled in cities. Alissa Walker, Curbed, "Lyft rides are now carbon-neutral—what does that mean for you?," 24 Apr. 2018 No company’s main source of profit can be described with a straight face as a negative externality. Alex Shephard, The New Republic, "Facebook’s Innocence Project," 10 Apr. 2018 Moreover, some policies are not as susceptible to externalities. Joseph Blocher, Vox, "A gun debate compromise: let cities and rural areas pass different laws," 24 Mar. 2018 This externality alone could wipe out a range of the benefits that bitcoin advocates imagine could result from the use of cryptocurrencies. Alexis C. Madrigal, The Atlantic, "Bitcoin Mining Turns Electricity Into Money," 12 Mar. 2018 Economists and urban planners should rejoice because AVs mean that, for the first time, the unwelcome externalities associated with cars can be fully priced in. The Economist, "Self-driving cars offer huge benefits—but have a dark side," 1 Mar. 2018 Our society is horrible at accounting for long-term externalities. Phillip Molnar, sandiegouniontribune.com, "Should the state gas tax be repealed?," 23 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'externality.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of externality

1673, in the meaning defined at sense 1

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The first known use of externality was in 1673

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