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

Perhaps one of the most significant cases of externalities is the extensive use of the military draft. David R. Henderson, WSJ, "Chicago’s Lesser-Known Free Marketeer," 13 Jan. 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 The reported ambiguity of the language has caused confusion among those who will be affected, and some have argued that preparing the new tax forms will open the door to other externalities. Bradford Betz, Fox News, "Churches, nonprofits balk at elimination of tax break; some lawmakers seek repeal," 28 July 2018 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

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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having a desire to acquire more things

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