SYA (Shut Your Ass): When someone talks so much bullshit or nonsense he is asked to stop talking or shut his ass so the nonsense or lies will stop or the shit stops leaking from his verbal asshole.
Alternate meaning: When someone tells you something so amazing or unbelievable or too good to be true that you are in awe and dismay that you tell them to shut their ass because you think its utter bullshit.
Dominic: I'm telling you i seen her with my own eyes, the chick in the car next to me was Kim Bassinger and she was checking me out!
Angel Baby: Shut Your Ass (SYA) Dom, you're such full of shit you wish that was her in that car checking you out, Keep drinking and Shimmy Sham
will start dancing nude in this mofo!