the word "retard" originally came from latin, a synonym of "slow". it entered the english language in the 15th century, and was used to refer to delaying or holding back in terms of progress or development. the word "decelerate" would succeed "retard" overtime. "retard" first became known as a medical term in the late 19th and early 20th centuries, when medical texts began to describe children with "retarded mental development". up until around the 1960s, the terms "moron", "idiot", "cretin" and "imbecile" were all genuine terms to refer to people with mental intellectual disabilities and low intelligence. these words were discontinued in that form when concerns arose that they were offensive, with "retard" and "retarded" replacing them. since then, the terms "handicapped" (united states) and "disabled" (united kingdom) have replaced "retard" and "retarded". in 2010, despite not typically being used in official context, "mental retardation" was still written in many of the united states' laws and documents, considered by many to be outdated. barack obama replaced the term with "intellectual disability" with the approval of rosa's law—which would require these laws and documents to phase out the terms with the "intellectual disability" term.