scientist
Usually, they are called a musician.
It is usually referred to as cyberbullying.
They are usually called the murder victim.
It's usually called "Recovered Memories".
Usually a generous or caring person.
At some point in the past someone decided to classify matter. Then someone noticed that there were some mixtures in which differences could be seen, these were called heterogeneous. And someone noticed that in other mixtures you could not see the differences. These were called homogeneous.
Memorial
Usually only if you are called as a witness.
You are usually called a Candidate
Usually someone who writes on a blog that isn't theirs is called a contributor or a guest blogger.
A member of the cavalry, usually called a "cavalryman" or "cavalier".
It is usually called enabling.