Dictionary.com
Thesaurus.com
Synonyms

intelligent

American  
[in-tel-i-juhnt] / ɪnˈtɛl ɪ dʒənt /

adjective

  1. having good understanding or a high mental capacity; quick to comprehend, as persons or animals.

    an intelligent student.

    Synonyms:
    bright
    Antonyms:
    stupid
  2. displaying or characterized by quickness of understanding, sound thought, or good judgment.

    an intelligent reply.

    Synonyms:
    smart, shrewd, discerning, apt, bright, alert, clever, astute
    Antonyms:
    stupid
  3. having the faculty of reasoning and understanding; possessing intelligence.

    intelligent beings in outer space.

  4. Computers. pertaining to the ability to do data processing locally; smart.

    An intelligent terminal can edit input before transmission to a host computer.

  5. Archaic. having understanding or knowledge (usually followed byof ).


intelligent British  
/ ɪnˈtɛlɪdʒənt /

adjective

  1. having or indicating intelligence

  2. having high intelligence; clever

  3. indicating high intelligence; perceptive

    an intelligent guess

  4. guided by reason; rational

  5. (of computerized functions) able to modify action in the light of ongoing events

  6. archaic having knowledge or information

    they were intelligent of his whereabouts

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Related Words

Intelligent, intellectual describe distinctive mental capacity. Intelligent often suggests a natural quickness of understanding: an intelligent reader. Intellectual implies not only having a high degree of understanding, but also a capacity and taste for the higher forms of knowledge: intellectual interests. See sharp.

Other Word Forms

  • hyperintelligent adjective
  • hyperintelligently adverb
  • intelligently adverb
  • nonintelligent adjective
  • nonintelligently adverb
  • preintelligent adjective
  • preintelligently adverb
  • quasi-intelligent adjective
  • quasi-intelligently adverb
  • semi-intelligent adjective
  • semi-intelligently adverb
  • superintelligent adjective

Etymology

Origin of intelligent

First recorded in 1500–10; from Latin intelligent- (stem of intelligēns, present participle of intelligere, variant of intellegere “to understand,” literally, “choose between),” equivalent to intel- (variant of inter- inter- ) + -lig- (combining form of leg-, stem of legere “to pick up, choose”; lection ) + -ent- -ent

Explanation

Humans? Intelligent! Potted plants? Not so much. Intelligent means smart, or having the ability to process and understand information (including dictionary definitions). Intelligent comes from a Latin word meaning "to understand, to gather," and intelligent creatures gather and make sense of information easily. Intelligent also refers to the ability to think. Intelligent objects, like speakers or software, seem to think in the way they react to change. If we’re looking for intelligent life on Mars, we want Martians who can reason. Intelligent also means showing good judgement, like an intelligent decision not to invite all those Martians to your birthday party.

Keep Reading on Vocabulary.com

Vocabulary lists containing intelligent

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

My best guess is that Cassidy and Kaine themselves — being the intelligent and diligent legislators they are — would prefer a serious approach and offer this proposal simply to move their colleagues to action.

From MarketWatch • Apr. 9, 2026

She said: "The family weren't pleased at all but they had a softer approach towards Violet partly because... she had mental health problems but she was also an incredibly intelligent woman."

From BBC • Apr. 7, 2026

And they must seem intelligent without actually being enterprising enough to stand out from the crowd of near-identical films.

From Salon • Mar. 29, 2026

But if you thirst for a sober-minded investigation into this ominous tool — one with an approach that treats you like the intelligent being you are — you’ll have to wait for AI doc 2.0.

From Los Angeles Times • Mar. 27, 2026

But having treated him through many ups and downs, Lebensohn believed that William was “an extraordinarily intelligent man” with “Manic Depressive Illness.”

From "The Woman All Spies Fear" by Amy Butler Greenfield