A word who's origin is made to be puzzling, but is really made famous by the Movie "Rocky" and by various rappers. Yo is a word deeply connected in the Philadelphia culture, therefore; no, it is not used only by "little black kids" or "wannabe suburbans" like the definitions before it has stated.

A history lesson about the word's popular use in Philly from the New York Times:
"In the 1930's a large proportion of the residents of South Philadelphia were Italian immigrants, mostly from the Campania region of southern Italy, the principal city of which is Naples.

In the Neapolitan dialect "guaglione" (pronounced guahl-YO-nay) signified a young man. The chiefly unlettered immigrants shortened that to guahl-YO, which they pronounced whal-YO. That was inevitably further shortened to yo. The common greeting among young Italian-American males was "Hey, whal-YO!", and then simply, "Yo!" And so it remains today."

Sorry for this long post, but I had to handle my business about my city.

And the "Yo" is the pronounciation of the word "you're," is usually spelled yo'.
"Yo man, that jawn was hot yesturday, yo."

"Yo, I can't believe they ran out of cherry wooder ice!"

"Yo! Come here!"
by Lili2344 August 1, 2006
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A slang term for car. It is Cockney rhyming slang - short for Yo-Yo Ma, which rhymes with car.
Bridget: Hey Jeff, let's go for a cruise in the yo yo!

Jeff: Fair enough!
by technology212 February 25, 2010
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a slang way of saying hello, usually friendly and casual
by Evil Penguin July 29, 2004
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the one word that can be added to almost any sentence and work
I need a book on how to sleep with a sheet yo.
by LittleLiblet February 21, 2003
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when you are skateboarding and you do a trick and land so hard that it feels like your nuts stretch down like a yo yo and then come back up and hit you.
damn dude i did that ollie off that ledge and got served the yo yo.
by tangent87 May 28, 2004
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