It means Hey You.
It is mainly used when addressing an individual in any given situation to get his or her attention.

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.

a streamlined fusion of the salutation "hey, yo" that goes over extremely well with the modern urban entrepreneur.

a response for a very suspect or homosexual comment.

often used as a gteeting in replacement of "hey yo"

This is a Nigerian name of the Yoruba dialect which means 'Joy'. It can be combined with other names.

Someone everyone wants to be cause he's sick at everything