If someone has an intellectual disability, it means that he or she learns and develops more slowly than other kids. At one time, intellectual disabilities were called “mental retardation.” Someone with an intellectual disability will have trouble learning and functioning in everyday life. This person could be 12 years old, but might not talk or write as well as a typical 12-year-old. He or she also is usually slower to learn other skills, like how to get dressed or how to act around other people.

An intellectual disability is a disability characterized by significant limitations both in intellectual functioning (reasoning, learning, problem solving) and in adaptive behaviour, which covers a range of everyday social and practical skills. This disability originates before the age of 18. Testing for an intellectual disability is usually done as part of an educational assessment.