There is something intrinsically pleasing to the notion of the familiar and widely-used word ‘cop’ having entered the language in unusual fashion:

What is the origin of the word “cop”? Wikipedia says that it is an acronym for “constable on patrol”. I have personally herd the phrase “citizen on patrol”. However, there’s another story that in early NYC, officers were noted for having copper buttons on their uniforms, so the word “copper” became slang for an officer which gets shortened to “cop”. That actually makes more sense to me, meaning that “constable on patrol” is probably just a backronym to make a derogatory slang term into an acceptable one.

But whatever we may want to believe, it just didn’t happen that way. “Cop” as a slang term for “police officer” is neither a shortening of “constable on patrol” nor of “citizen on patrol.”

We’ve said it before, but it bears saying again: only a few common English words truly have acronymic pedigrees, and virtually all of those date from the latter half of the 20th century and later. Though terms that have been part of the English language for centuries may well have fascinating backstories (and many do), they rarely began their linguistic lives as acronyms, words formed by combining the initial letter(s) of a compound term or phrase.

The word ‘cop’ also did not enter the slang lexicon as an allusion to the highly polished buttons (which some say were made of copper) on American turn-of-the-century police uniforms or on those worn by the first London police force of the 1820s. It also doesn’t refer to the metal various police badges or shields were made from.