Sizeism or size discrimination is discrimination based on a person's size. Size discrimination usually refers to extremes in physical size, such as very tall or short; extremely thin or fat.
This type of discrimination can take a number of forms, ranging from refusing to hire someone because they are considered to be too short or too tall, to treating overweight and underweight individuals with disdain.
There aren't currently any specific anti-discrimination laws that have been put in place to prohibit sizeism, despite the issue being extremely prevalent. Sizeist stereotypes (such as "overweight people are lazy" or "tall people can play basketball") are often ingrained in modern society.
In the US, the list of anti-discrimination acts does not specifically include sizeism as an offense.
Sizeism can be based on height, weight or both, and so is often related to height and weight-based discrimination but is not synonymous with either. Depending on where in the world one is and how one lives his/her life, people may have a tendency to be especially tall, slender, short, or plump, and many societies have internalized attitudes about size. As a general rule, sizeist attitudes imply that someone believes that his or her size is superior to that of other people and treat people of other sizes negatively.
Examples of sizeist discrimination might include a person being fired from a job for being overweight or exceptionally short though their work was unaffected.
Sizeism often takes the form of a number of stereotypes about people of particular heights and weights.
Sizeist attitudes can also take the form of expressions of physical disgust when confronted with people of differing sizes and can even manifest into specific phobias such as cacomorphobia (the fear of fat people), or a fear of tall or short people. Sizeism, being a newly recognized discriminatory stance, is usually observed by those who are its targets.