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Synonyms

detect

American  
[dih-tekt] / dɪˈtɛkt /

verb (used with object)

  1. to discover or catch (a person) in the performance of some act.

    to detect someone cheating.

  2. to discover the existence of.

    to detect the odor of gas.

  3. to find out the true character or activity of.

    to detect a spy.

  4. Telecommunications.

    1. to rectify alternating signal currents in a radio receiver.

    2. to demodulate.


detect British  
/ dɪˈtɛkt /

verb

  1. to perceive or notice

    to detect a note of sarcasm

  2. to discover the existence or presence of (esp something likely to elude observation)

    to detect alcohol in the blood

  3. to extract information from (an electromagnetic wave)

  4. obsolete to reveal or expose (a crime, criminal, etc)

"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

Usage

What are other ways to say detect?

To detect is to discover something hidden or unknown. When should you use detect over learn, discover, or ascertain? Find out on Thesaurus.com. 

Other Word Forms

  • detectability noun
  • detectable adjective
  • detecter noun
  • detectibility noun
  • detectible adjective
  • predetect verb (used with object)
  • undetectable adjective
  • undetectably adverb
  • undetected adjective
  • undetectible adjective

Etymology

Origin of detect

First recorded in 1400–50; late Middle English, from Latin dētēctus “discovered,” past participle of dētegere “to uncover, discover,” from dē- de- + tegere “to cover”; thatch

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.

Rival U.S. firms are sharing information to detect so-called adversarial distillation attempts that violate their terms of service.

From Los Angeles Times • Apr. 10, 2026

With current instruments, it may already be possible to detect them.

From Science Daily • Apr. 8, 2026

Software vulnerabilities exposed by Mythos were often subtle and difficult to detect without AI, according to Anthropic.

From Barron's • Apr. 7, 2026

Major social-media platforms have struggled to detect and label AI-generated content.

From The Wall Street Journal • Apr. 6, 2026

Even though I can’t visually see him, I detect that he is reading off a tablet.

From "A Rover's Story" by Jasmine Warga