Term invented by writers to devalue the work of other writers they don't like, by claiming they copied their feelings or writing subjects. The use of this term is especially common on social media communities with a large amount of amateur, self-publishing writers that are incapable of creating an original concept.
Seeing as Betty wrote a poem about a blooming flower as a simile for love just hours after I wrote mine. We really should band together to call her out on concept plagiarism.