Homicide is simply when a human is killed by another human Murder is homicide where there was criminal intent to commit the homicide. "Murder" and "Homicide" are often used interchangeably, but there is a technical legal difference. Assassination is a murder of a specific target, usually in order to make some sort of political statement or to gain the upper hand in warfare. Assassination targets are always people of importance. Hope this helped :)

I'm presuming you know what murder means, so I'll just tell you about the other two. Assassination is the public killing of a prominent person, usually a politician. The purpose of assassination is to make a political or moral statement. Homicide is a technical/legal term. It has a broader meaning than 'murder' as it can, for example, include the lesser charge of 'manslaughter', and the non-criminal act of killing someone in self-defence.

All of them mean that someone kills someone else but I think murder is the most common. Assassination is usually used to talk about someone who was famous or very popular (Such as the JFK assassination) and homicide is a technical word, for example police officers and detectives would use it but I would probably not.