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externality

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noun ex·ter·nal·i·ty \ˌek-ˌstər-ˈna-lə-tē\

Definition of externality

plural

externalities

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

1673

First Known Use of externality

1673

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