manslaughter

n. killing of a human being; unintentional killing of one person by another, killing which was not premeditated (Law)

Manslaughter is the legal term for the killing of a human in a manner considered by law as less culpable than murder.The law generally differentiates between levels of criminal culpability based on the mens rea, or state of mind. This is particularly true within the law of homicide, where murder requires either the intent to kill, a state of mind called malice or malice aforethought, which may involve an unintentional killing but with a willful disregard for life.
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Manslaughter, n the act of causing the death of another person; categorized as involuntary or voluntary. [more]Manslaughter - Community and Resources

Noun
1. homicide without malice aforethought
(hypernym) homicide
(hyponym) chance-medley

(n.)
The unlawful killing of a man, either in negligenc/ or incidentally to the commission of some unlawful act, but without specific malice, or upon a sudden excitement of anger.
  

(n.)
The slaying of a human being; destruction of men.