1916, Ralph Barton Perry, Present philosophical tendencies, But according to the theory of the externality of relations, terms acquire from their new relations an added character, which does not either condition, or necessarily alter, the character which they already possess.
(countable) A thing that is external relative to something else.
(economics, countable) An impact, positive or negative, on any party not involved in a given economic transaction or act.
2007, George W. Bush, S:Executive Order 13422, "(1) Each agency shall identify in writing the specific market failure (such as externalities, market power, lack of information) or other specific problem that it intends to address (including, where applicable, the failures of public institutions) that warrant new agency action, as well as assess the significance of that problem, to enable assessment of whether any new regulation is warranted."
