When you start watching one YouTube video and it spirals out of control into hundreds of different videos.

Term coined by Anthony B, and Jeff R.
I watched a video on puppies and went down a YouTube hole and ended on Russian firecracker fishing.
by Crumpetlova December 25, 2016
After watching a video, the list of suggested or related videos. Contains a list of sixty videos that are similar to the video you just watched. Often refers to when someone continually watches referred videos.
I searched a video on how to solve a rubiks cube, but I got stuck in a Youtube hole and ended up watching a video about how to make homemade chicken noodle soup.
by nameistaken August 25, 2009
It is what happens when you watch an embedded YouTube video on another site and then watch a couple dozen related videos that are displayed after the previous video completes. The rabbit hole effect is only encountered after at least an hour has passed and you regain your sense of temporal awareness. This effect usually is followed by, "How the fuck did i get to this video?"
"Dude, I was watching the Macho Claw mod video and an hour later, I realized that I'd watched at least 10 videos about My Little Ponys without remembering how I got there. The YouTube Rabbit Hole is a dangerous thing."
by BlindBastard January 6, 2016
1. When you start watching something and end up on a different topic hours later.
2. When you waste time on youtube instead of working cause you want to escape reality.
3. Youtube Algorithm (Slang)
- Hey! You watching adult YT videos!
: Nah man, I was just searching for "how to attract girls" and end up here.
- That's how youtube rabbithole works pal.

- I should escape youtube rabbit hole, it keeps me awake late night.
: Why don't you learn something instead.
- I was learning about war history and couple minutes later, Jedi VS Sith Rap battle!
by naisty October 5, 2019