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Synonyms

detective

American  
[dih-tek-tiv] / dɪˈtɛk tɪv /

noun

  1. a member of the police force or a private investigator whose function is to obtain information and evidence, as of offenses against the law.

adjective

  1. of or relating to detection or detectives.

    a detective story.

  2. serving to detect; detecting.

    various detective devices.
detective British  
/ dɪˈtɛktɪv /

noun

    1. a police officer who investigates crimes

    2. See private detective

    3. ( as modifier )

      a detective story
"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

adjective

  1. used in or serving for detection

  2. serving to detect

"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

Etymology

Origin of detective

First recorded in 1830–40; detect + -ive

Explanation

Whether it's a police detective who investigates crimes or a private detective hired to find a missing person, a detective is someone whose job is to find out hard-to-get information. Detective comes from the Latin root detectus meaning to uncover or expose. Detectives detect, or discern and uncover the truth, the way a dog might detect an odor and uncover a bone. Sherlock Holmes, perhaps the most famous detective in fiction, used disguises, deductive reasoning and forensics to solve crimes. "When you have eliminated the impossible, whatever remains, however improbable, must be the truth," he famously said.

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Vocabulary lists containing detective

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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.

The ranks of the four serving officers being investigated for gross misconduct are commander, detective chief inspector, detective sergeant and detective constable.

From BBC • Apr. 14, 2026

Yet the Metropolitan Police’s lead detective, Mr. Keefe writes, seemed “maddeningly incurious.”

From The Wall Street Journal • Apr. 10, 2026

Thomas Pynchon hasn’t lost a step with his 1930s tale about the misadventures of a Milwaukee cheese heiress and the detective that travels to proto-fascist Budapest to find her.

From Los Angeles Times • Apr. 9, 2026

A veteran homicide detective named Jim Ford tried to retrace Cynthia’s last steps.

From Slate • Apr. 6, 2026

“No. He’d say that a good detective needs to figure out the IFs.”

From "Trouble at the Arcade (The Hardy Boys: Secret Files, #1)" by Franklin W. Dixon

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.