Feminism is literally defined, it is the belief in equal rights and treatment. It isn't a religion, but a singular, one-sentence principle and idea. I tried to use your Christian comparison so you could understand my point better, but I'm just going to say that the idea of feminism and the complexity of a religion are apples to oranges. Feminism is an idea with a singular definition, and anything contrary, any other definition someone puts to it, is a separate concept or an inspiration from the original idea. Saying that feminism doesn't have a clear definition is like saying atheism or vegetarianism doesn't have a clear definition. Atheists do not follow spiritual beliefs. Vegetarians do not eat meat. They might have their differing reasons, purposes, beliefs about that concept, but they all fall under that definition because it is clearly defined as so, no ifs and or buts. Any variation in either of these concepts goes by a different name entirely, just as there's words to describe different degrees of gender support that are not equal on both sides. The label of "feminist" does not hold the complexity of the label "Christian". It just means someone who believes in genders not being an issue when it comes to treatment and socioeconomical rights. It is important, beautiful, but it is simple. And I understand that people don't like being labelled because they see faults in other people holding the same principle, but it's important not to tarnish and openly disassociate that label because some people are shite and are not following that principle.