Feminism refers to a diverse variety of beliefs, ideas, movements, and agendas for action. Here is what I find to be the core similarities among those using the term for their own beliefs, ideas, movements and agendas for action:
A. Feminism consists of ideas and beliefs about what culture is like for women just because they are women, compared to what the world is like for men just because they are men. In ethical terms, this form or aspect of feminism is descriptive. The assumption in feminism is that women are not treated equally to men.
B. Feminism also includes ideas and beliefs about how culture can be and should be different -- goals, ideals, visions. In ethical terms, this form or aspect of feminism is prescriptive.
C. Feminism includes ideas and beliefs about the importance and value of moving from A to B -- a statement of commitment to behavior and action to produce that change.
D. Feminism also refers to a movement -- a collection of loosely connected groups and individuals committed to organized action, including changes in behavior of members of the movement and persuasion of others outside the movement to make change.
In other words, feminism describes a culture in which women, because they are women, are treated differently than men, and that, in that difference of treatment, women are at a disadvantage; feminism assumes that such treatment is cultural and thus possible to change and not simply "the way the world is and must be"; feminism looks to a different culture as possible, and values moving towards that culture; and feminism consists of activism, individually and in groups, to make personal and social change towards that more desirable culture.