manslaughter (n.) Look up manslaughter at Dictionary.com
mid-14c., " act, crime, or sin of killing another human being," in battle or not, from man (n.) + slaughter (n.). Replaced Old English mannslæht (Anglian), mannslieht (West Saxon), from slæht, slieht "act of killing" (see slay). Etymologically identical with homicide, but in legal use usually distinguished from murder and restricted to "simple homicide."