Feminist
A word that you'll get ten different definitions for if you ask ten different people to define it.
Most likely, each person will be 100% sure theirs is the "one true definition," and that all all other definitions are false.
Marcie: Vicky asked me whether or not I'm a feminist.

Kyle: What did you say?

Marcie: I asked her which definition of feminist she was using. There are millions of them.