in·​ves·​ti·​ga·​tor | \ in-ˈve-stə-ˌgā-tər How to pronounce investigator (audio) \
plural investigators

Definition of investigator

: one who investigates something: such as
a detective a private investigator Debra Winger plays the investigator who becomes fixated on identifying a killer …— Margaret Rauch
b : a person who conducts experiments or is involved in scientific studies for research the lead investigator in a clinical trial For dialect recording, it is best for the investigator to take down as full and accurate notes as possible without slowing down the pace of the interview.— Ravin I. McDavid Jr.

Synonyms for investigator


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First Known Use of investigator

1538, in the meaning defined above

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Time Traveler for investigator

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The first known use of investigator was in 1538

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Cite this Entry

“Investigator.” The Dictionary, Merriam-Webster Inc., Accessed 17 January 2020.

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Comments on investigator

What made you want to look up investigator? Please tell us where you read or heard it (including the quote, if possible).


a plan in which a last survivor takes all

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