The only way to stop the feminists from playing word games with the word "feminism", is to claim that word, and control the meaning of it on our own account. We know what the word means to US, in our world, for our purposes -- and nothing else would serve our purposes. If you are a feminist, you are free to converse with other feminists on the assumption that "feminism" means what you say it means. But when you wander into the non-feminist zone, you had best understand that you have entered a speech community with different lexical conventions. This will prevent needless misunderstanding.
From henceforth, feminism is what WE say it is. And feminist, if you don't like what WE say feminism is, then get back inside the feminist clubhouse, which is the only zone where your self-definition operates.