Street
fly cop
What does fly cop mean?
A 'fly cop' (or 'elbow') is a plainclothes police detective, 'fly' meaning sharp or cunning.
"Watch the corner, there's a fly cop working the crowd."
Origin
American underworld slang, 19th century; 'fly' = alert/knowing.
Frequently asked questions
What is a 'fly cop'?
A plainclothes police detective. 'Fly' here means sharp, alert, or cunning.
Where does 'fly cop' come from?
It's 19th-century American underworld slang, where 'fly' meant knowing or streetwise.
How do you use 'fly cop'?
As a warning about an undercover officer: 'Watch the corner, there's a fly cop working the crowd.'
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