private eye

American  

noun

Slang.

1. a private detective.

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private eye British  

noun

1. informal a private detective

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private eye Idioms  

1. A privately employed detective, as opposed to one working for the police or another authority. For example, The children loved stories about private eyes, and Janey wanted to become one. This expression comes from the term private investigator, the “i” of investigator being changed to “eye,” which plays on the idea of a person looking into things. [1930s]

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Etymology

Origin of private eye

1935–40; eye, allusive phonetic rendering of I, abbreviation of investigator

Example Sentences

The author of “Gravity’s Rainbow” sends a private eye on the trail of a missing heiress in a complex, comic, Prohibition-era caper.

From The Wall Street Journal • Oct. 3, 2025

But Paco Ignacio Taibo II is best known for his fictional alter ego: Héctor Belascoarán Shayne, a one-of-a-kind private eye confronting injustice, corruption and crime in the noir depths of 1970s Mexico City.

From Los Angeles Times • Jan. 6, 2025

The article focused on Robert Winnett, the British journalist poised to take over The Post’s newsroom in November, and described his links to a private eye who used unethical media practices to land big exclusives.

From New York Times • Jun. 17, 2024

The great Richard Roundtree, who died this week at 81, played which private eye in five movies over a 50-year period?

From Slate • Oct. 27, 2023

As one private eye put it, he might be a “miserable snake,” but he was also “the silent, secret, and effective Avenger of the outraged Majesty of the Law when everything else fails.”

From "Killers of the Flower Moon" by David Grann

Related Words

• P.I.
• inquiry agent
• private detective
• private dick
• private investigator
• sleuth