1. Literally, to propel saliva from one's mouth in the direction of someone or something. Someone in the crowd spat at the policeman as he tried to calm them down. We sat on the overpass, spitting at the cars driving underneath.

2. To treat someone or something with scorn, contempt, or disregard. I trusted you with my secrets, then you spit at me by going up on the witness stand to testify against me! I always feel like I need to go out and give 100% of my effort and energy whenever I perform on stage. Anything less, and it feels like I'm spitting at all the devoted fans who came to see me.