A concise answer: being a feminist means believing in equal rights, opportunities, and dignity for all genders, and actively challenging systems and beliefs that create or uphold gender-based inequality. Key ideas

• Core aim: gender equality in political, economic, social, and cultural life.
• Not about hating men or reversing oppression; it's about leveling the playing field so everyone can participate fully.
• Inclusive in practice: recognizes that other forms of oppression (race, class, disability, sexuality, etc.) intersect with gender, so feminist work seeks justice for all who are marginalized.
• Varied approaches: feminism is diverse and evolving, with different theories, strategies, and priorities (for example, focusing on bodily autonomy, wage equality, representation, or anti-violence frameworks).

How to understand it in practice

• Everyday equality: advocating for equal pay for equal work, fair parental leave, and reproductive rights.
• Representation: pushing for diverse voices in leadership, media, and policymaking.
• Intersections: acknowledging how race, class, disability, and other identities shape unequal experiences, and prioritizing those most marginalized within feminist aims.
• Critique and change: questioning longstanding norms, laws, and institutions that sustain gender bias, and supporting reforms or grass-roots actions to address them.

If you’d like, I can tailor a definition to a specific context (e.g., academic, activist, or workplace), or summarize how different feminist perspectives (liberal, socialist, radical, intersectional) differ in emphasis.