Meanings
- Harry PotterslanguncountablelifestyleA subgenre of Harry Potter fanfiction in which Severus Snape is the biological father of Harry.
Unlike the other Severitus fanfics analysed in this chapter, there is not a simple progression from dislike to affection and family feeling.
2011, Suzanne Passmore, "Rereading the Magical World of Harry Potter: Fanfiction as an Alternative Critical Modality", thesis submitted to the University of Western Australia, page 522 more examples
Arguably Snape's lifelong obsession with Lily in canon is more disturbing than the least imaginative and most derogatory Severitus conception, the drunken one night stand.
2007 September 5, A. G. McDowell, “Re: The Future of Fan Fiction”, in alt.fan.harry-potter (Usenet)[…] and in making Lily break her vows to James, Severitus fanfiction authors undermine the status of the heteronormative family in the original series.
2015, A. J. Koning, "The Famous and Their Followers: Fanfiction as an Alternative Form of Literary Criticism", thesis submitted to Utrecht University, page 22
Origin
In the early 2000s, a fan going by the pseudonym Severitus (presumably constructed from Severus + -itis) issued a challenge requesting fanfics with several specific elements, including Snape being revealed as Harry's true father. This became known as the Severitus Challenge, which was later shortened to Severitus, and came to refer exclusively to the paternity trope.
Full word history & related roots →Cite this entry
Severitus. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/Severitus
“Severitus.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/Severitus. Accessed November 4, 2026.
WatkinsX Dictionary, s.v. “Severitus,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/Severitus.
Source: Severitus on Wiktionary, CC BY-SA 4.0.