ex·​ter·​nal·​i·​ty | \ ˌek-ˌstər-ˈna-lə-tē How to pronounce externality (audio) \
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 The best way to reduce carbon emissions is to incorporate that externality into the market’s functions, rather than declaring that growth is the enemy. Robert Colvile, National Review, "The Problem with the Climate Strike’s Leaders," 24 Sep. 2019 And those solutions often have ripple effects in society, and create externalities that must be carefully considered. Kush Saxena, Quartz, "Engineers need a required course in ethics," 8 Nov. 2019 Negative externalities Could a band of social scientists really wreak so much havoc? The Economist, "When economists ruled the world," 31 Aug. 2019 In many, however, a pickup truck, a freeze box, and a couple of rifles will get the job done — and without any of the negative externalities that mark the more modern, industrial approach. Charles C. W. Cooke, National Review, "Why Shoot Prairie Dogs?," 11 July 2019 Concentrating low-income people in a geographic area can lead to negative externalities, such as low performing schools. San Diego Union-Tribune, "Econometer: Should San Diego developers be allowed to put low-income apartments in different buildings?," 2 Aug. 2019 But as Demsetz pointed out, companies aren’t the only ones that impose negative externalities. David R. Henderson, WSJ, "Chicago’s Lesser-Known Free Marketeer," 13 Jan. 2019 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 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

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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Cite this Entry

“Externality.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/externality. Accessed 19 Feb. 2020.

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