# externality

> English word · Noun · IPA /ɛkstəˈnælɪti/ · frequency rank #86,259

## Definitions
1. The state of being external or externalized.
2. A thing that is external relative to something else.
3. An impact, positive or negative, on any party not involved in a given economic transaction or act.

## Etymology
From external + -ity. In the economic sense coined by British economist Alfred Marshall in 1890.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/externality