I think this is the difference between manslaughter and homicide. Hitting someone without intent to kill isn't homicide.
Homicide only means the killing happened at the hands of another. There is nothing in regard to culpability or intent.
There are different phrases that mean different things in different states. Some places call murder in the first degree capital murder. Likewise, manslaughter can come in varying degrees.
Hitting an elderly man in the head with a megaphone even without intent to seriously harm him, let alone kill, would be manslaughter. It is not murder, that would require intent.