When there is 3 or more people being involved in being "played". It can be that one person is playing another, and that the original player is also getting played, and that the last person has no idea what is going on, and thinks its a normal relationship.
An example Play Line would be that Tierza is playing Michael, and he doesn't know it, but Tierza is being played by Curtis and she doesn't know it either.
A slang for 'Down Syndrome', but not in a literal sense. Can be used to describe one self when they are being an idiot.
*note* As made famous by Laura F.
"I was so DS yesterday that I forgot how to spell Laura"