Definition from Wiktionary, the free dictionary
From the name of an intentionally over-the-top character in the 1973 Star Trek parody fan fiction A Trekkie's Tale by Paula Smith.
- (fandom slang, usually derogatory) A fictional character, usually female, whose implausible talents and likeability weaken the story.
2010 August 3, Ta-Nehisi Coates, “A Whole New World”, in The Atlantic:
- Bella may be a Mary Sue, but if we don't identify with her, and even if we do, there's no other interpretive place for us in the universe.
2015 January 20, Sian Cain, “Why a non-white Nancy Drew could be amazing”, in The Guardian:
- She was a mashup of ideals that made her feel very fake; a Mary Sue who was popular, pretty, athletic, artistic, all the while loved by everyone who met her.
2015 December 19, Tasha Robinson, “With Star Wars' Rey, we've reached Peak Strong Female Character”, in The Verge:
- So here's a radical suggestion: instead of being concerned about whether her Mary Sue flawlessness is a problem, why not, just this once, enjoy it for what it is?
- Used especially with reference to fan fiction.