There are many different definitions of disability, some of which vary by geography and local legislation (as with the UK’s Equality Act, Canada’s Disability Reference Guide, and the USA’s Americans with Disabilities Act). No universal definitions exist, but one commonly used definition comes from the UN’s Convention on the Rights of Persons with Disabilities, which states that “disability results from the interaction between persons with impairments and attitudinal and environmental barriers that hinder their full and effective participation in society on an equal basis with others”.
Some additional perspectives and resources on defining disability include:
Disabled World, Disabilities: Definition, Types and Models of Disability and The WHO’s International Classification of Functioning, Disability, and Health both look at classifying different types of disabilities and how they effect disabled people.
Self Defined by Tatiana Mac : a modern dictionary of words and how they define us, which seeks to provide more inclusive, holistic, and fluid definitions to reflect the diverse perspectives of the modern world.