Uchronia is currently an English word-in-formation, a neologism, that is sometimes used in its original meaning as a straightforward synonym for alternate history, a genre of speculative fiction that reimagines historical events going in new, imaginary directions. However, it has also begun to refer to other related concepts.
In the Spanish, French, German, Portuguese, Italian, Catalan, and Galician languages, the words uchronie, ucronia, and ucronía are native terms for alternate history from which derives the English loanword uchronia. The word is composed of the Greek prefix οὐ- ("not", "not any", and "no") and the Greek word χρόνος (chronos) "time", to describe a story set in "no time"; it was formed...