Numerous slang terms exist for the police. Many slang terms for police officers are decades or centuries old with lost etymologies. One of the oldest, 'cop', has largely lost its slang connotations and become a common colloquial term used both by the public and police officers to refer to their profession.

The word "cop" is derived from the verb sense "to arrest". Thus, "someone who captures", a "copper", was shortened to just "cop". It may also find its origin in the Latin 'capere', brought to English via the Old French caper.

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