crap on (someone or something)

rude slang To speak disparagingly or discouragingly about someone or something. A: "Why do you always have to crap on my dreams, huh?' B: "Because the odds of you becoming a famous actor are slim to none!" Everyone on this forum needs to stop crapping on people just for having different opinions! I'm not going to agree with every decision you make, so don't crap on me for having a mind of my own.