It doesn't matter whether you like the term. Language is a decentralised system, you can individually change the meaning of a word, but if people don't adopt it you will use it alone and nobody will understand you. A language is how it is spoken and how it is spoken evolves naturally.
Capitalism is just a system with individual ownership of capital goods. This is how 99% of the people call it. We already have a word for what you describe as capitalism and that is fascism.