Where does “злокачественный” come from?

злокачественный (Russian) comes from Russian зло, from Old East Slavic зъло, from Proto-Slavic *zъlo — evil.

злокачественный (Russian): malignant tending to cause death

Definitions

  1. malignant tending to cause death

Ancestry of “злокачественный”, step by step

злокачественный traces back through two separate lines of ancestry.

via Russian зло

StepLanguageWordMeaning
1Russianзлоevil, bad, wrong; harm; malice, rage, anger,...
2Old East Slavicзъло—
3Proto-Slavic*zъloevil

via Russian ка́чество

StepLanguageWordMeaning
1Russianка́чествоquality
Every word from Proto-Slavic *zъlo →Every word from Old East Slavic зъло →Every word from Russian зло →