When your mate does something stupid and just looks at you with a stupid smile
Person 1: *licks a used condom*
Person2: da fuck...
Person 1: *stupid smile*

Person 2: Fucking why????

Person 1: *turns away*
Person 2 is left very confused and makes a definition for 'Fucking why' on urban dictionary
by GazzerBaa February 17, 2016
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What someone says when they have done something for the purpose of maliciously disrupting another person(s) motive, intentions, life, job, etc, and the victim asks that someone why they did it.
NEWS AGENCY: We have hired a new science editor.

Bob: Welcome to the team, Freeman. We need you to start by editing this paper on climate change. Exxon is one of our top sponsors and they have told you to remove the bit on 80% efficiency solar panels and make it look like oil does not harm the environment.

Freeman: Ok.

3 days later:

Bob: FREEMAN! You included the bit on 80% efficiency solar panels, you made the bit on oil seem even more against the environment, and then you proved that Exxon bribes us! WHY?!

Freeman: Why? FUCK YOU, that's why.
by The Lion's Word July 20, 2011
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A response to a question of the practicality of something which is clearly overkill, it implies that the one who uses the phrase to answer the question of 'why' knows full well that it is overkill, and overkilling for overkill's sake was their intent.

(The examples probably describe it better)
Q: Why would you build an aircraft carrier that flies?
A: Because fuck you, that's why

Q: Why would you need a 6-core CPU?
A: Because fuck you, that's why

Q: Why would you make an automatic grenade launcher?
A: Because fuck you, that's why
by gnerd October 11, 2011
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A smart/ funny way to tell off a person that asks a smart/dumb question that has to have the word "Why" in it.
Teacher: Dylan why didn't you finish your homework?!
Dylan:Why?
Teacher:Yes.
Dylan:Fuck it thats why.
by D-Meister June 23, 2006
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The correct response to a smart arsed sarcastic question, usually from your partner.
Gemma :"You have apparently took a wrong turn and are now going in the wrong direction. Phils house is the other way, why did you do this?"
John : "Fuck you that's why!"
by KingPryle September 23, 2010
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Douche: yo, why can't I get some of that azz?

Hot chick: because fuck you that's why.
by Supadupaflye69 August 12, 2014
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so I am all out of words and so little fucking ideas tighten my mind desperately
Kidnapper ask for candy: I don't fucking know why I writing this shit no more,, take candy
by bitchdipshit February 20, 2021
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