PD can you explain it to a white brother just what emotion that emoticon expresses?
It's an emote of former tough guy Suge Knight getting knocked the fuck out at a club

The emote is meant to express the most extreme level of shock or being stunned. As in when a joke, sarcastic quip, or comment moves from being funny to being so real, so potent that the only way you can express yourself is by laying on the floor sprawled out in utter disbelief.
exampleJoe: Hey William, how is your computer program going?
William: About as well as Windows 8's performance
Joe: *dead*
exampleJane: What do you want to do tomorrow?
Sally: I was out all night! My knees hurt
Marge: I wonder why...
Jane: *dead*
exampleBoogie: ...and then she told me she'd call and never did
Tiesto: I know that feel bro
Bepbo: So do I
BrandNew: You guys need a girl that you don't have to call to talk to. Like a next door neighbor or..
Tiesto: A sister?
Boogie, Bepbo: *dead*