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private eye

See more synonyms for private eye on Thesaurus.com
noun Slang.
  1. a private detective.

Origin of private eye

1935–40; eye, allusive phonetic rendering of I, abbreviation of investigator
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for private eye

sleuth, agent, cop, snoop, tail, P.I., bloodhound, dick, peeper
British Dictionary definitions for private eye

private eye

noun
  1. informal a private detective
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
Idioms and Phrases with private eye

private eye

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]

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