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.

Definitions of moron

n a person of subnormal intelligence

changeling, cretin, half-wit, idiot, imbecile, retard
a person suffering from Down syndrome (no longer used technically in this sense)
Type of:
simple, simpleton
a person lacking intelligence or common sense

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