The best replacement for manslaughter is homicide.

The best alternatives to manslaughter are rated as following:
★★★★★  homicide
★★★  negligent homicide
★★★  murder
★★★  involuntary manslaughter
★★  vehicular homicide
★★  2nd degree murder
★★  self defense
★  second degree murder
★  accidental death
★  2nd degree
★  second degree
★  1st degree
★  murder 2
★  manslaughter
★  voluntary manslaughter
★  culpable homicide
  involuntary
  first degree murder
  criminally negligent homicide
  vehicular manslaughter
  criminal negligence
  death by dangerous driving
  third degree murder
  third degree

Your alternative for manslaughter is not listed? Suggest!
Speaking about manslaughter, one probably shouldn't forget about gross negligence.

Other search terms related to manslaughter and their ratings are:
★★★★★ gross negligence
★★★ diminished responsibility
★★ laughter
You have in mind a companion for manslaughter and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of manslaughter in all years. Click on graph for more.
manslaughter
homicide
negligent homicide