Ableism (/ˈeɪbəlɪzəm/; also known as ablism, disablism (British English), anapirophobia, anapirism, and disability discrimination) is discrimination and social prejudice against physically or mentally disabled people. Ableism characterizes people as they are defined by their disabilities and it also classifies disabled people as people who are inferior to non-disabled people. On this basis, people are assigned or denied certain perceived abilities, skills, or character orientations.

There are stereotypes which are either associated with disability in general, or they are associated with specific impairments or chronic health conditions (for instance the presumption that all disabled people want to be cured, the presumption that wheelchair users also have an intellectual disability, or the presumption that blind people have some special form of insight). These stereotypes, in turn, serve as a justification for discriminatory practices, and reinforce discriminatory attitudes and behaviors toward people who are disabled. Labeling affects people when it limits their options for action or changes their identity.

In ableist societies, the lives of disabled people are considered less worth living, or disabled people less valuable, even sometimes expendable. The eugenics movement of the early 20th century is considered an expression of widespread ableism.

Ableism can be further understood by reading literature which is written and published by those who experience disability and ableism first-hand. Disability studies is an academic discipline which is also beneficial when non-disabled people pursue it in order to gain a better understanding of ableism.

Discrimination on the basis of mental disorders or cognitive impairments is known as sanism.

Originating from -able (in disable, disabled) with influence of able (ultimately from Latin habilis) and -ism (in racism, sexism); first recorded in 1981.

Ableism in Canada refers to a set of discourses, behaviors, and structures that express feelings of anxiety, fear, hostility, and antipathy towards people with disabilities in Canada.

The specific types of discrimination that have occurred or are still occurring in Canada include the inability to access important facilities such as infrastructure within the transport network, restrictive immigration policies, involuntary sterilization to stop people with disabilities from having offspring, barriers to employment opportunities, wages that are insufficient to maintain a minimal standard of living, and institutionalization of people with disabilities in substandard conditions.