You-Know-Who 

The name in the Harry Potter wizarding world for Lord Voldemort. He has also been called "He Who Must Not Be Named", "Lord Thingy", and other appellations of the sort.

Ron: "Hey, Hermione, I heard that You-Know-Who is trying to find Harry. D'you think he wants to kill him?"

You-Know-Who by Lizzi K April 21, 2006

You-Know-Who 

A person, usually an acquaintance, who you find completely detestable. The mere mention of their name is enough to fill you with a feeling of dread, while an encounter with this person inevitably leaves a cloud of misery hanging over an otherwise pleasant day. This term is derived from a common reference to Lord Voldemort from J.K. Rowling's Harry Potter series.

"I bumped into You-Know-Who the other day...that basically ruined my week."

You-Know-Who by Bumpalicious February 6, 2010

you know who 

a shady character

Larry: I am heading back home, I will be cool.

Harvey: Well, watch out for you know who as you walk through that neighborhood on your way home.

you know who by cut the cards September 5, 2022

you know who 

The Dark Lord, y'know, the one who doesen't have a kickass mace and a ring fetish...

"You know, I see the oppurtunity for a union here..." - Lord Voldemort (AKA "You Know Who", or "The Dark Lord") to Sauron (AKA "The Dark Lord") and Darth Vader (AKA "The Dark Lord")

you know who by Alexander Girard April 8, 2006

you know who 

Dick Trickle, a very unsuccessful NASCAR driver (in SportsCenter terminology). Probably started because his real name is too obscene to say on cable TV.

"Jeff Gordon won his third race this year, and you know who finished his best race of the season in 37th place." -ESPN anchor

Fred: "Doc, I think I caught an STD from this dirty whore I nailed last weekend."
Doc: "Hmmm...what are your symptoms?"
Fred: "I've got an itchy red rash, it burns when I pee, and I've got some real nasty you know who."
Doc: "Dick Trickle, eh? Yep, looks like a classic case ofherpegonnosyphiltitis to me. Bend over, we're gonna have to do a rectal examination."
Ricky Martin: "Giggidy giggidy!"

you know who by Nick D July 13, 2004

You Know Who 

a pronoun used to say something about your crush without saying their real name

Raul: Guess who's behind you.
Hugo:Who?
Raul: jasmi-
Hugo: Say "You Know Who" you moron!
Raul: k...

You Know Who by dark_avenger877 March 21, 2019

You Know Who 

A guy with a country accent who is missing a chunk of hair in one spot. You Know Who also always wears black or white.

Look! It's You Know Who! His hear looks really nice today! How does my hair look?

You Know Who by California Mountain Snake October 6, 2004