I'm no Lawyer but here is England's definition:
Manslaughter
Manslaughter is primarily committed in one of three ways:
- Killing with the intent for murder but where a partial defence applies, namely loss of control, diminished responsibility or killing pursuant to a suicide pact.
- Conduct that was grossly negligent given the risk of death, and did kill ("gross negligence manslaughter"); and
- Conduct taking the form of an unlawful act involving a danger of some harm that resulted in death ("unlawful and dangerous act manslaughter").