extropy

English

Etymology

First coined to serve as an antonym of entropy, substituting its en- element (representing the prepositional prefix ἐν (en), en, “in” in its Ancient Greek etymon ἐντροπία (entropía), entropia, “a turning towards”) with ex- (representing the Ancient Greek ἐξ (ex), ex, “out of”, “from”); because ἐξ (ex) takes the form ἐκ (ek) when prefixed to an element beginning with τ (t), the analogical spelling is ectropy (or, alternatively, ektropy), as if after the Ancient Greek *ἐκτροπία (ektropía, “a turning out of”).

Noun

extropy (countable and uncountable, plural extropies)

1. Negentropy.
   • 1999, Wolfgang Hofkirchner, The Quest for a Unified Theory of Information: Proceedings of the Second International Conference on the Foundations of Information Science, Psychology Press, →ISBN, page 272:

     Extropy uptake, extropy output and entropy production. [...] Jin is the incoming extropy flow, while Jout is the outgoing one. Extropy inflow / outflow is the extropy of the incoming / outgoing material […]

Derived terms

• extropian

Further reading

• Extropy on Wikipedia.Wikipedia