Where does “cop-killer” come from?

cop-killer (English) comes from English killer, from English -er, from Middle English -er, from Old French -er, from Latin -āre, from Proto-Italic -āō, from Proto-Indo-European -eh₂yéti, from Proto-Indo-European -yéti — he, she.

cop-killer (English): A person who deliberately kills an on-duty police officer

Definitions

  1. A person who deliberately kills an on-duty police officer

Ancestry of “cop-killer”, step by step

cop-killer traces back through two separate lines of ancestry.

via English killer

StepLanguageWordMeaning
1EnglishkillerOne who or that which kills; That which causes...
2English-erA person or thing that does an action indicated...
3Middle English-eragentive suffix; agent noun suffix
4Old French-erAlternative form of -ier, verbal suffix;...
5Latin-ārefirst conjugation
6Proto-Italic-āōForms primarily denominative verbs
7Proto-Indo-European-eh₂yétiCreates iterative/ frequentative/ intensive...
8Proto-Indo-European-yétiCreates intransitive, often deponent,...
9Proto-Indo-Europeanyé-
10Chichewaiyehe, she

via English cop

StepLanguageWordMeaning
1EnglishcopTo capture or arrest someone
2Middle Englishcopsummit; top, tip, topmost part; top of the head,...
3Old Englishcop
4Proto-West Germanic*koppvessel, container, bowl
5Proto-Germanickuppazround object; orb; vessel; container; bowl;...
6Proto-Indo-Europeangup-round object, knoll
7Proto-Indo-Europeangew-to bend, curve, arch, buckle; to bend, to curve;...
Every word from Chichewa iye