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1. who are you?
A rhetorical question, generally in the form of an insulting chant, accompanied by finger-pointing; meant as abuse to a single person or team performing in front of a crowd, by indicating that they are unknown and insignificant.

Abuse is aimed at two groups:
1) An unknown competitor, whose relative anonymity is highlighted even further.
2) Paradoxically, a well-known competitor whose high credibility and status is undermined in an act of defiance by pretending to regard the competitor as unknown or insignificant.

Abuse is aimed in two ways:
1) When the competitor is announced.
2) When the competitor is performing badly.

The phrase is often used in sport, particularly at football matches in the UK.
"Who are you?" is usually pronounced "Who are ya?!", with emphasis on the word "are".

1) Liverpool (big football club) v Grimsby (small football club):

Announcer : "On to the pitch comes...Grimsby"
Liverpool fans : "Who are ya?! Who are ya?! Who are ya?!..."

2) Leyton Orient (small football club) v Chelsea (big football club)

The Chelsea player, Didier Drogba, misses a clear chance of scoring a goal and falls over badly, clutching his knee in agony.

Leyton Orient fans : "Who are ya?! Who are ya?! Who are ya?!..."
2. who are you?
a rhetorical phrase that insinuates that the person who is being spoken to is either strange or a moron.

the person being spoken to with usualy reply with their full name but you're never actually looking for an answer, hence it being rhetorical.
who are you?
by megHan Jun 2, 2004 add a video
3. who are you?
this is a common expression for next morning reaction to a one night stand laying just beside you.
obvious statement; you find some stranger in your bed, and what's the first thing you ask? "who are you?"
by NLU Sep 7, 2005 add a video
4. who are you?
Godly saying spoken bye keith in mall monkeys.
Fakeem: Man I'd like to tap dat
Keith: Who are you?!
by Matt da Fat Sep 15, 2003 add a video
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