A person who intentionally takes the joy of another person and brutally murders it with no remorse.
Girl: Yesh, finally Full Metal Alchemist. Oh how I've longed for you. *kisses television*
Mom: No FULL METAL ALCHEMIST. Japan is evil.
Girl: Geez Mom, you're such a kill-joy!

Girl: Yesh, No school because of snow!
Weather Man: Looks like school is back in session due to the sudden elevation of tempurature.
Girl: Geez Mr. Meteorologist Man Guy, you're such a kill-joy.
by Buttonsinfallcolours August 09, 2006
Photos & Videos
Top Definition
Someone who wants to ruin someone elses fun.
The killjoy tattled to the apartment manager, after he saw Mike enter his apartment with a gorgeous woman at midnight.
by Ronald Clifford Buckman August 09, 2003
Reference to "Danger Days: The True Lives of the Fabulous Killjoys", the (as yet to be released) album by My Chemical Romance.

Outsider fighting against social/corporate suffocation.


"Killjoys, make some noise!"

Search "Na Na Na trailer" on YouTube for the best definition/example.
by Elph7777 October 01, 2010
a person who takes the fun out of things for other people
You killjoys need to loosen up. I want you to have some fun this time.
by Light Joker May 17, 2005
The new super heros of the world, out to bring colour and spread the message of the ugly truth to the rest of this conformist society.
We were created by My chemical romance thanks to their new album "Danger days - the true lives of the fabulous Killoys"
The original Killjoys consist of Pary Poison (Gerard Way) Jet star (Ray toro) Fun ghoul (Frank iero) and Kobra kid (Mikey way).
The names of these killjoys have also been rumoured to have something to do wih President JF kennedy, this is due to PJFK the first leters of he bands killjoy names. there is also a kennedy reference in the popular single from he album "NANANA", and the album its self was released on kennedys 50th aniversary. coincedence?
Many of the fans of my chemical romance (the MCRmy) have now adapted the name Killjoy and have even given theirselves killjoy names of heir own such as "NeonDeath" or "Rainbowninja". Killjoys typically dress in bright coloured biker jackets, tight jeans, biker boots, bright bandanna/ helmet/ mask, and wear shoe-laces tied round their wrists or wear gloves.
Killjoys carry a brighly coloured Ray-Gun for fighing the enemy (Draculoids).
Killjoys often have brightly coloured hair (inspired by gerard way's crimson red hair).
The Killjoys of the MCRmy will fight for what is right for what they believe and for the band that they love.
"Killoys, make some noise!"

person 1 : "whats she wearing?"
person 2: "her killjoy oufit."
person 1: "whats that?"
person 2 :" its an MCR thing".

(See Danger Days- the true lives of the fabulous killjoys)
by Amyneondeathkilljoy June 28, 2011
One who kills fun and/ or joy and happiness.

Also see party pooper
Dude!! I was about to get laid, but then my dad walked in and freaked out. He's such a killjoy.
by Senor Anon May 06, 2008
1)someone who doesn't want others to enjoy something because it is in his/her taste.

2) someone who doesn't like happiness, laughter or fun especially when the person is not involved/invited and comes in to ruin it.
1) James is always coming in and cutting off the game because he sucks at it, he is such a killjoy.

2) Whenever we are laughing, joking or playing a fun game, it bugs jim's father so much that he runs downstairs and ruins it for us. tsk, tsk...such a killjoy.
by COOLMASTER X October 15, 2009
somebody who ruins fun for other people
I wont bother making a christmas turkey next year

Bloody hell! Stop being a bloody Killjoy
by mickmickman July 10, 2008
Free Daily Email

Type your email address below to get our free Urban Word of the Day every morning!

Emails are sent from daily@urbandictionary.com. We'll never spam you.