Noun
State of being external; exteriority
separation from the perceiving mind.
Source: Webster's dictionarythe outwardness of the world Source: Internet
Externality An externality exists when a person makes a choice that affects other people in a way that is not accounted for in the market price. Source: Internet
An externality can be positive or negative, but is usually associated with negative externalities in environmental economics. Source: Internet
A common example of such an externality is double marginalization. Source: Internet
An externality is an effect of some activity on an entity (such as a person) that is not party to a market transaction related to that activity. Source: Internet
Because the unpleasantness of the work is not internalised, being born by the slave rather than the owner, it is a negative externality and leads to over-use of slaves in these situations. Source: Internet