Please note that the context of terms are ever-changing.
These definitions are based on Merriam-Webster Dictionary and, referenced June 2020.

ABLEISM  |  noun
discrimination or prejudice against individuals with disabilities

ANTI-RACISM  |  noun
Opposed to racism. (see Racism below).

1) the theory that the overlap of various social identities, as race, gender, sexuality, and class, contributes to the specific type of systemic oppression and discrimination experienced by an individual (often used attributively):
"Her paper uses a queer intersectionality approach."

2) the oppression and discrimination resulting from the overlap of an individual’s various social identities:
"the intersectionality of oppression experienced by black women."

LGBTQIA+  |  abbreviation
lesbian, gay, bisexual, transgender, queer/questioning (one's sexual or gender identity), intersex, and asexual/aromantic/agender

Note that gender and sexual identity are fluid and on a spectrum, therefore a finite acronym will not cover all possible ways someone can present or identify themselves; the "+" at the end of the term is a way to be inclusive and recognize the validity of someone outside of the standard seven-letter abbreviation.

PRIVILEGE  |  noun
a right, immunity, or benefit enjoyed only by a person beyond the advantages of most:
"the privileges of the very rich."

RACISM  |  noun

Racism is most commonly used to name a form of prejudice in which a person believes in the superiority of what they consider to be their own “race” over others. This most often takes the form of believing that those with other skin colors—especially darker skin colors—are inferior physically, intellectually, morally, and/or culturally, and mistreating and discriminating against them because of this. Such a belief typically promotes the notion that white people are “the default”—that whiteness is “normal” and that people with other appearances are the ones who are “different” (and “inferior”).

The word racism is also used to mean a system of oppression based on this kind of prejudice that is thought to be embedded into the fabric of society and its institutions, resulting in ongoing mistreatment and injustice in many, many forms. This is often called systemic racisminstitutional racism, or structural racism. These terms imply that such racism is upheld by laws, policies, traditions, and institutions—and the people who keep them in place.

When used in this way, racism typically refers to a system that has oppressed people of color all over the world throughout history. Such a system is often thought to operate through white people using the advantages that the system gives them (often called white privilege) to maintain their supremacy over people of color (often called white supremacy). Particularly in the U.S., it’s used to refer to a system that has historically oppressed and continues to oppress Black people, Native (also called Indigenous) Americans, and other people of color, including Latinx, Asian, Middle Eastern, and Australian Aboriginal and other Oceanic peoples.

Other forms of bigotryintolerance, and xenophobia, such as anti-Semitism and Islamophobia, are often considered to be rooted in racism.