What does unintelligent mean?
Unintelligent means lacking intelligence, understanding, or the ability to reason effectively. In everyday use, it describes people who make foolish or poorly considered decisions, but it can also be applied to animals, machines, systems, and designs. Its force often lies in the implication that a person or thing has failed to act with appropriate thought or judgment. The word is sometimes confused with unintelligible, but those terms focus on different problems: an unintelligent person lacks intelligence, while an unintelligible message cannot readily be understood. Although commonly treated as a direct negative form of intelligent, unintelligent also carries a broader connotation of irrationality, thoughtlessness, or poor planning. It is therefore useful when describing conduct or systems that appear capable in form but fail to show sound reasoning in practice.
adjectiveLacking intelligence, understanding, or the ability to reason; often implying foolishness or poor judgment.
- Not possessing sufficient intelligence, understanding, or reasoning ability.
- Exhibiting foolish, thoughtless, or poorly judged behaviour.
"The proposal was rejected because its safety plan was plainly unintelligent."
"The student made an unintelligent decision by ignoring the instructions."
"The bridge's unintelligent design made it vulnerable during severe storms."
A machine can be called unintelligent without being broken: it may simply lack the capacity to understand, learn, or reason.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does unintelligent come from?
Unintelligent was formed in early modern English by combining the negative prefix un- with intelligent. Intelligent ultimately comes through French from Latin intellegens, a form of intellegere meaning 'to understand'. The same Latin foundation produced related English words such as intelligence and intelligible, while intelligibility preserves the same root in another grammatical form.
Related word forms
How unintelligent is actually used
The term is generally neutral to strongly negative and can describe people, animals, machines, systems, or plans. It usually suggests deficient reasoning or poor judgment rather than simply a lack of knowledge.
Easily confused with unintelligent
Unintelligent means lacking intelligence or sound judgment, whereas unintelligible means impossible or difficult to understand.