External may refer to: *

External (mathematics) The term external is useful for describing certain algebraic structures. The term comes from the concept of an external binary operation which is a binary operation that draws from some ''external set''. To be more specific, a left external binary ...

, a concept in abstract algebra *

Externality In economics, an externality or external cost is an indirect cost or benefit to an uninvolved third party that arises as an effect of another party's (or parties') activity. Externalities can be considered as unpriced goods involved in either co ...

, in economics, the cost or benefit that affects a party who did not choose to incur that cost or benefit *

Externals The Externals are a group of fictional characters appearing in American comic books published by Marvel Comics. Considered a rare subspecies of mutants, most of them were X-Men antagonists. The original, unused name for the group was to be Th ...

, a fictional group of X-Men antagonists

See also