I connotationally interpret your question as: "what are the community norms about bad things?" You're not giving us enough information so that we could know what you're talking about, and you're asking our blind permission to condemn behaviour you disagree with.

I don't have an answer here, just a note that this question actually contains two questions, and it would be good to answer both of them together. It would also be a good example of using rationalist taboo. A: What are the community norms for defining sexism? B: What are the community norms for dealing with sexism (as defined above)? Answering B without answering A can later easily lead to motivated discussions about sexism, where people would be saying: "I think that X is [not] an example of sexism" when what they really wanted to say would be: "I think that it is [not] appropriate to use the community norm B for X".