Definition & Meaning of "moron"in English

What is the origin of the term "moron" and how is it used?

"Moron" is an English term that appeared in the early 20th century, originally as a technical psychological term for mild intellectual disability, but its medical usage is now obsolete. In modern slang, it refers to a very stupid or foolish person, divorced from any clinical meaning. The term is used in informal, critical, or humorous contexts to insult someone's intelligence or decisions. It is mildly to moderately derogatory but not vulgar, commonly understood as a strong, casual insult rather than a highly offensive curse.