"Oum Ya... / ...قوم يا" - Lebanese Slang - Literally means "Get up you...". Used towards someone who is over-exaggerating or lying. Similar to the english dismissing expression "yeah whatever".
Sample conversation:
Person 1: "I managed to lose 20 kilos in one month"
Person 2: "Oum Ya... (قوم يا)"
Person 1: "seriously, and then he went on about how he's been promoted and has a team of 100 people reporting to him now!"
Person 2 (disbelievingly): "illo eh man, illo eh..."
Baddi Nazzil el Sama 3al Ared - بدي نزل السما عالارض : Lebanese Slang, of unknown origin. Meaning: "I want to bring the sky down to earth". This slang is used to infer great anger which makes the person try the impossible to change the situation.