Meaning
What does Is That a JoJo Reference? mean?
Is that a JoJo reference?, also encountered as Is this a JoJo reference?, is an ironic rhetorical question online, that is dropped into the comment section of pictures and posts, that are in fact a reference to JoJo’s Bizarre Adventure, an anime and manga series.
Origin
What's the origin of Is That a JoJo Reference??
The earliest case of the question emerged on 4chan’s /a/ (anime) board on September 13th, 2009.
“Is that a JoJo reference?” is a common question, since, being one of the oldest and longest running anime and manga series, JoJo’s Bizarre Adventure is referred to in a lot of settings, including other mangas, animes as well as video games.
Spread & Usage
How did Is That a JoJo Reference? spread?
On April 22nd, 2015, Reddit user, SamuraiDDD shared a post, inquiring about animes that have a good JoJo reference, inciting a lot of users to write sarcastic replies in the thread.
The phenomenon turned common on Reddit and 4chan, mostly on boards or subreddits related to anime or manga.

External resources
- Urban Dictionary – A Jojo reference