Diversity: recognizes the wide variety of cultural, ethnic, religious, gender, economic, ability, educational and life experiences (to name a few) humans represent. Practicing diversity means demonstrating we are stronger as we value and embrace the richness that human differences bring to our educational, professional, political and social endeavors. (adapted from Simmons College)
Equity: fairness and impartiality (see definition). We use the word equity to demonstrate that no single way of being human or human experience is privileged above another. Equity means we work to ensure that individuals and groups with varying gender identities, religious beliefs, economic status, physical or mental abilities, and ethnic and racial identities are fairly represented and treated equally with every other individual and group.
Inclusion is action. Inclusion is doing the work to empower and involve all individuals and groups; it is active participation by all members in the work and life of a community. It is welcoming, inviting, and celebrating the unique experiences, skills, wisdom, and contributions of all.(adapted from Simmons College)
Equality is about ensuring that every individual has an equal opportunity to make the most of their lives and talents. It is also the belief that no one should have poorer life chances because of their identity or circumstances. Equality recognizes that historically certain groups of people with protected characteristics such as race, disability, sex and sexual orientation have experienced discrimination (adapted from the Equality and Human Rights Commission)
Behind the White Picket Fence: Power and Privilege in a Multiethnic Neighborhood by 
Encyclopedia of Diversity and Social Justice by 
Safe Spaces, Brave Spaces: Diversity and Free Expression in Education by