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Synonyms

investigation

American  
[in-ves-ti-gey-shuhn] / ɪnˌvɛs tɪˈgeɪ ʃən /

noun

  1. the act or process of investigating or the condition of being investigated.

    Synonyms:
    exploration, scrutiny
  2. a searching inquiry for ascertaining facts; detailed or careful examination.

    Synonyms:
    exploration, scrutiny

investigation British  
/ ɪnˌvɛstɪˈɡeɪʃən /

noun

  1. the act or process of investigating; a careful search or examination in order to discover facts, 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 does investigation mean? An investigation is a thorough search for facts, especially those that are hidden or need to be sorted out in a complex situation. The goal of an investigation is usually to determine how or why something happened. Investigations are usually formal and official. The word is commonly associated with police investigations of criminal activity, but it is used in many other contexts to refer to the process of investigating—systematically finding and examining evidence. Example: After a six-month investigation, this news organization uncovered widespread corruption.

Related Words

Investigation, examination, inquiry, research express the idea of an active effort to find out something. An investigation is a systematic, minute, and thorough attempt to learn the facts about something complex or hidden; it is often formal and official: an investigation of a bank failure. An examination is an orderly attempt to obtain information about or to make a test of something, often something presented for observation: a physical examination. An inquiry is an investigation made by asking questions rather than by inspection, or by study of available evidence: an inquiry into a proposed bond issue. Research is careful and sustained investigation.

Other Word Forms

Etymology

Origin of investigation

First recorded in 1400–50; late Middle English investigacio(u)n from Latin investīgātiōn- (stem of investīgātiō ). See investigate, -ion

Explanation

If something has gone missing, conduct an investigation to find it. To do this, seek out details associated with its disappearance, asking questions and gathering evidence in order to find out what happened to it. If you watch a lot of detective shows, it won’t surprise you to learn that the noun investigation traces back to the Latin words in-, meaning “into,” and vestigium, meaning “footprint, track.” An investigation may not always involve people looking for footprints at a crime scene, but that methodical gathering of details and other evidence associated with a crime or wrongdoing is at the heart of any investigation.

Keep Reading on Vocabulary.com

Vocabulary lists containing investigation

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.

According to data from the Aeronautical Accidents Investigation and Prevention Center, Brazil recorded 153 air accidents in 2025, with a death toll of 62.

From Barron's • May 5, 2026

He later founded a private investigation firm, the Aenigma Investigation Agency, based in Westlake Village.

From Los Angeles Times • May 1, 2026

Last week, Federal Bureau of Investigation Director Kash Patel sued the Atlantic for defamation after it published an article highlighting concerns about his drinking habits and professional conduct.

From The Wall Street Journal • Apr. 27, 2026

Denmark's Accident Investigation Board arrived at the scene during the morning and Inspector Morten Pedersen of North Zealand police said they would be working together to find out what had happened.

From BBC • Apr. 23, 2026

“There’s one more thing we should do,” the Colonel said as we played a video game together with the sound on—just the two of us, like in the first days of the Investigation.

From "Looking for Alaska" by John Green