What is animation?

I love posing this question to my class or even in a professional conversation.  What comes back with the grandest of intent is some sideways explanation of the "Illusion of Life" or "Acting through Movement".  The question confuses some at least those who think before they spew their twelve principles all over the floor. 

The reason any thinking artist is confused is that animation itself defines two aspects of the form, it is both the practical application and action of frame by frame artistic torture as well as the gestalt, the overarching whole potato of the medium, the animated film.  One can say "I am an animator", but animator's don't make up the entire process.  They are only the actors, they do not write the script, they do not score the music or mix the track, they don't paint the backgrounds.

What is animation?  Animation is the culmination of just about every art form there is, that is what animation is.