1935-40;eye, allusive phonetic rendering of I, abbreviation of investigator
Examples from the web for private eye
The big question now is who will play the roguish private eye as he tackles cases no one else wants to handle.
He declined to return phone calls, and slammed the door in the face of the private eye they'd hired to track him down.
His iconoclastic and likable private eye survives every crisis thrown his way.
Any private eye or vandal can buy your mobile-phone records.
British Dictionary definitions for private eye
private eye
noun
1.
(informal) a private detective
Slang definitions & phrases for private eye
private dick
noun phrase
A private detective; a private investigator; pi(entry form 1908+, variant 1938+)
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 ]