Informal. a person who is notably stupid or lacking in good judgment.
I wonder why they elected that narrow-minded moron to Congress.
Psychology. (no longer in technical use; now considered offensive) a person of borderline intelligence in a former and discarded classification of intellectual disability, having an intelligence quotient of 50 to 69.
a foolish or stupid person
a person having an intelligence quotient of between 50 and 70, able to work under supervision
More context on moron Calling someone a moron is all in good fun, right? Not so much. While moron can sound like a simple schoolyard taunt, the term was originally used by psychologists to classify someone as having mild intellectual disabilities. What’s more, prominent psychologists, notably Henry H. Goddard, who used the label moron promoted eugenics. Moron is no longer in use as a medical term, and it’s offensive and ableist to equate someone you think is acting foolish to a person with a disability. If knowing the history of moron has got you reflecting on your word choices, this slideshow, "These Common Words Have Offensive Histories," discusses many other words whose place in your vocab you may want to reconsider.
An Americanism first recorded in 1905–10; from Greek mōrón, neuter of mōrós “foolish, dull”
When your little brother does something that is both stupid and infuriating, you'll have to bite your tongue to keep from calling him a moron. A moron is an unkind way to describe someone who is foolish and unintelligent. The word moron was an official term in the early 1900s, used to describe a person of low intelligence — specifically, an "adult with a mental age between eight and twelve." It became a popular insult in the 1920s, and gradually stopped being used as a medical term, until moron was only an informal way to put someone down.
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
US forces use the Rota naval base and Moron air base in southern Spain under an agreement signed in 1953 under the dictatorship of General Francisco Franco.
From Barron's • Mar. 4, 2026
A defence barrister told Dungannon Magistrates' Court that 55-year-old Moron was going to collect his mother from the airport.
From BBC • Sep. 6, 2024
The mummies were found in unusual positions and with a mix of textiles that pointed to the influence of Spanish colonials, added field manager Manuel Moron.
From Reuters • Oct. 13, 2022
Born in Moron in the Cuban province of Ciego de Avila in 1945, Rivero co-founded the literary magazine “El Caimán Barbudo” in 1966.
From Seattle Times • Nov. 15, 2021
Or if I called Moron “Dean” in front of everyone, it'd damage my own standing.
From "Black Swan Green" by David Mitchell
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
