Intersectionality aka Identity Politics is a theoretical framework for understanding how aspects of a person's social and political identities (e.g., gender, sex, race, class, sexuality, religion, disability, etc. etc.) combine to create unique modes of discrimination and privilege. Intersectionality identifies advantages and disadvantages that are felt by people due to a combination of factors. (Def: Wikipedia)
Another way of putting it and using the Intersectionality Credibility Coefficient. You get one credibility point for any category which applies. (Supposedly) the more points the more weighty your argument and righteousness is.
Example: A gay black lesbian would be given a threefold advantage over a white man in any dispute of any type regardless of truthfulness, factuality, intellect, achievement, social status etc.