What does stupid mean?
“Stupid” means lacking intelligence, good judgment, or sensible thought. It describes people who fail to understand something, but it is also commonly applied to actions, decisions, mistakes, questions, and results that appear foolish or badly planned. The word can sound insulting when used about a person, so more formal alternatives such as “unwise” or “ill-judged” are often preferable in careful writing. In informal contexts, however, “stupid” is widely used with a direct, emphatic tone, as in calling an obvious mistake “stupid.” Its historical roots lie in Latin, where the related adjective stupidus meant dull-witted or insensate. The term remains common in everyday English, though its tone can range from casual self-criticism to a blunt personal insult.
Lacking intelligence, good judgment, or sensible thought; foolish or unwise.
"That was a stupid decision."
Common in both formal and informal English, but potentially insulting when used to describe a person.
Informally, a person regarded as stupid or foolish.
"The children called him a stupid, but he was the only one who had noticed the problem."
Informal and potentially insulting; often used as a contemptuous label.
“Stupid” has been an English insult for centuries: it entered English from Latin stupidus, meaning insensate or dull-witted.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does stupid come from?
The English word entered Middle English from Latin stupidus, an adjective meaning dull-witted, insensate, or foolish. Latin stupidus developed from a wider Indo-European root associated with being stunned or deprived of sensation, also reflected in English words such as “stupor” and “stupefy.” The meaning expanded over time from intellectual dullness to include lack of judgment and thoughtlessness.
Related word forms
How stupid is actually used
The word can be insulting when directed at a person, though it is often used in casual speech to describe a foolish action or decision. In formal writing, “unwise,” “ill-judged,” or “thoughtless” may be more suitable.
Easily confused with stupid
The adjective describes foolish or unwise behavior, whereas the noun is an informal, often insulting term for a person considered foolish.