externality

1. (uncountable) The state of being external or externalized.Examples: "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."uncountable

2. (countable) A thing that is external relative to something else.countable

3. (economics, countable) An impact, positive or negative, on any party not involved in a given economic transaction or act.Examples: "Waste is a negative externality arising from consumption."; ""(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.""; "Pigouvian taxes are meant to internalize ‘externalities’, generally understood to be positive or negative side-effects from economic production that are not reflected in the price of production."countable