verb (used with object)

to discover or catch (a person) in the performance of some act: to detect someone cheating.
to discover the existence of: to detect the odor of gas.
to find out the true character or activity of: to detect a spy.
  1. to rectify alternating signal currents in a radio receiver.
  2. to demodulate.

Origin of detect

1400–50; late Middle English < Latin dētēctus (past participle of dētegere), equivalent to dē- de- + teg(ere) to cover + -tus past participle suffix
Related formsde·tect·a·ble, de·tect·i·ble, adjectivede·tect·a·bil·i·ty, de·tect·i·bil·i·ty, nounpre·de·tect, verb (used with object)un·de·tect·a·ble, adjectiveun·de·tect·a·bly, adverbun·de·tect·ed, adjectiveun·de·tect·i·ble, adjective

Synonym study

2. See learn. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for detect

Contemporary Examples of detect

Historical Examples of detect

  • In more than one case, we seem to detect an actual portrait.

  • How often, my dear, have you and I endeavoured to detect and censure this partial spirit in others?

    Clarissa, Volume 2 (of 9)

    Samuel Richardson

  • He could detect a design upon it when nobody else had any perception of the fact.

    Little Dorrit

    Charles Dickens

  • The eye could not detect one creature in the group free from the smear of blood.

    A Tale of Two Cities

    Charles Dickens

  • The spy had kept his eyes open, but had been able to detect no sign.

    A Tale of Two Cities

    Charles Dickens

British Dictionary definitions for detect


verb (tr)

to perceive or noticeto detect a note of sarcasm
to discover the existence or presence of (esp something likely to elude observation)to detect alcohol in the blood
to extract information from (an electromagnetic wave)
obsolete to reveal or expose (a crime, criminal, etc)
Derived Formsdetectable or detectible, adjectivedetecter, noun

Word Origin for detect

C15: from Latin dētectus uncovered, from dētegere to uncover, from de- + tegere to cover
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

Word Origin and History for detect

early 15c., from Latin detectus, past participle of detegere "uncover, expose," figuratively "discover, reveal, disclose," from de- "un-, off" (see de-) + tegere "to cover" (see stegosaurus). Related: Detected; detecting.

Online Etymology Dictionary, © 2010 Douglas Harper