1. a timeline that is different from that of our own world, usually extrapolated from the change of a single event; the genre of fiction set in such a time.
- 1954 Mag. of Fantasy & SF (Feb.) № 40: Here is yet another adroit variant [...] with a startling footnote to the alternate history of our own Old West.
- 1967 A. Norton Operation Time Search № 6: You have heard of the alternate history theory — that from each major historical decision two alternate worlds come into being.
- 1992 M. Resnick Intro. Alternate Presidents № ix: A growing sub-genre of the field is the Alternate History story: what if Jesus had never lived, what if the Spanish Armada had destroyed the British fleet, what if the South had won the Civil War?
- 2002 SFRA Rev. Jan.–Feb. № 7/1: I have watched SFRA grow and develop for most of its history, and I have heard and read the ideas and dreams of its members [...]. In some "alternate history" of SFRA, perhaps these dreams have already been fulfilled.
- 1992 Locus (Aug.) № 4/1: Alternate histories fit into the science fiction field because their history connects back to some moment of our past.
- 1993 P. Nicholls J. Clute & P. Nicholls Ency. of SF № 1293/1: Only HW [Howard Waldrop] would have written [...] an alternate history (featuring 4 alternate worlds) with time travel from a dystopic future, Amerindian Mound Builders, Aztec Invaders, ancient Greek merchants in power-driven boats and much more.
- 2002 P. Heck Asimov's SF (Sept.) № 137/1: Here's an alternate history based on the assumption that a series of comet impacts in the mid-nineteenth century forced the British empire to relocate the center of its government to India.
