SF&F

Speculative fiction is an umbrella genre encompassing narrative fiction with supernatural or futuristic elements. This includes the genres science fiction, fantasy, horror and supernatural fiction, as well as their combinations. The broader usage of the term is attributed to Robert Heinlein, who referenced it in 1947 in an editorial essay, although there are prior mentions of speculative fiction or its variant "speculative literature".

Speculative fiction as a category ranges from ancient works to both paradigm-changing and neotraditional works of the 21st century. Speculative fiction can be recognized in works whose authors' intentions or the social contexts of the versions of stories they portrayed is now known, since ancient Greek dramatists such as Euripides (ca. 480–406 BCE) whose play Medea seems to have offended Athenian audiences when he fictionally speculated that shamaness Medea killed her own children instead of their being killed by other Corinthians after her departure, and whose Hippolytus, narratively introduced by Aphrodite, Goddess of Love in person, is suspected to have displeased his contemporary audiences because he portrayed Phaedra as too lusty.

In historiography, what is now called speculative fiction has previously been termed "historical invention", "historical fiction", and similar names. It is extensively noted in literary criticism of the works of William Shakespeare as when he co-locates Athenian Duke Theseus and Amazonian Queen Hippolyta, English fairy Puck, and Roman god Cupid across time and space in the Fairyland of its Merovingian Germanic sovereign Oberon in A Midsummer Night's Dream.

...
Wikipedia