TUMA stands for Thumb up my ass. This is said when waiting for someone for a long time, who doesn't seem to be going anywhere.
Person 1: I'm coming just let me to this one thing.
Person 2: You aren't coming, you've been there with me waiting here forever.
Person 1: No, I'm coming just wait a second.
Person 2: Come on! I'm waiting with my TUMA!