homicide comes from Latin homicidium ('manslaughter') and homicida ('murderer'), from homo ('man, human') + caedere ('to cut, kill'), via Old French homicide. The path is chiefly one of transmission: the word passes through the named languages and forms, with each stage preserving part of the modern shape. In present English, the noun sense is "the killing of one person by another", so the historical development ends in a clearly identifiable modern dictionary use. The same base also appears in related forms such as suicide, genocide, and patricide, and in derivatives such as homicidal and homicidally. Its semantic neighborhood includes murder, manslaughter, killing, and slaying, which helps locate the modern sense without adding a separate etymological claim. The named historical forms include Latin homicidium, Latin homo, and Latin caedere.