Fanfic Glossary A/B/O (Alpha/Beta/Omega)

What Does A/B/O (Alpha/Beta/Omega) Mean?

Fic Type

An alternate universe genre, also called Omegaverse, in which people have a secondary gender of Alpha, Beta, or Omega with distinct biological and social roles. It typically explores pack dynamics, heightened instincts, and hierarchy-driven relationships.

A/B/O (Alpha/Beta/Omega) in Practice

A/B/O emerged from the Supernatural fandom around 2010, originally in kink meme prompts, and spread until it became one of the most recognizable AU genres on AO3. The worldbuilding varies enormously between authors: some treat the dynamics as pure romance scaffolding, while others use them to interrogate consent, bodily autonomy, and social inequality. Common conventions include scenting, bonding marks, and biological cycles, though every fandom adapts the framework differently. The genre is divisive — some readers filter it out entirely while others read little else — which is why it is almost always clearly tagged. The term Omegaverse has since crossed into published romance fiction and even been the subject of real-world copyright litigation.

Example usage

"I never thought I would read A/B/O, but this author's worldbuilding converted me in one chapter."

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