Hypnosis
is the effect produced by the hypnotism skills of a hypnotist.
Defining hypnotism as a function of hypnosis, the state
that is produced by the hypnotist... is like defining a light source by focusing
on whatever it is shining on. It's confusing because the light can shine upon
many different things and reflect in many different ways.
A more useful definition is:
Hypnotist: A person who knowingly and artfully
changes someone's state of mind using hypnotism.
Hypnotism (descriptive) / Hypnotize (active):
The process of using specific communication skills to change someone's state
of mind. What a hypnotist does.
Hypnosis: The effect produced by a hypnotist using
hypnotism/while hypnotizing. The effect is characterized by a shift in
attention from external to internal and a change in, or suspension of,
critical thinking that allows responding to internal thoughts as
external events.