Discussions of nomenclature and category are neverending, and I have no wish to embroil myself, nor to flounder where earlier, braver souls have succeeded admirably, but in an earlier post I pointedly and repeatedly use the italicized French “fantastique” instead of the English word fantastic. For me, the fantastique refers to something quite narrow and almost culturally specific, far more so than fabulism, literary fantasy, the archaic Anglicized “fantastic,” or any of today’s more popular literary terms. It is not a market category, as fantasy and science-fiction in their most inclusive senses appear to have become. It is rooted in history and roughly bounded by formal structure. The fantastique is set in a world we know (most commonly consensual reality, depicted using realism’s formal codes) on which phenomena from a world we do not know (usually the supernatural, also depicted realistically—but because in the context of the tale this is the only way we know to describe it) briefly intrudes; these phenomena recede without a trace of explanation. Essentially, it is formally realist with non-realist content, the latter constituting an exception, incursion, or violation within it.
By contrast fabulism is a much broader term, defining itself largely by exclusion (non-realist content) and includes the cousin genres whose borders Todorov, Caillois, and Schneider wrangled over: the marvelous (merveilleux), which is closer to the English sense of “fantasy” in being set in a patently unreal world, and the uncanny, best illustrated by Gothic literature in which outright impossible events or merely an atmosphere of foreboding are eventually resolved by rational causes. (Schneider embraces both these wings as hyphenated forms of fantastique, pushing its definition toward fabulism.) The “weird tale,” a nomenclature far from universally recognized, would come, were it not for its emphasis on horror, closest to the French fantastique, out of which it arguably developed by way of the English Decadents.