As defined on Fanlore...
Dead Dove: Do Not Eat is a warning or tag that is used and interpreted in multiple different ways in different areas of fandom.
The phrase comes from a meme referencing the 2003 Arrested Development episode "Top Banana", in which Michael Bluth opens a paper bag labelled "DEAD DOVE DO NOT EAT" and, upon discovering that there is a dead dove inside the bag, says, deadpan, "I don't know what I expected."
It is most often defined as one of two things:
- This fanwork features depictions of "problematic" content; OR
- This fanwork is clearly labeled and you know exactly what you'll find