What is a antonym for compendium?

An expendium, maybe. Though realistically speaking, it doesn't exist. Hypothetically speaking though, if it did exist, it could be one of a few things:

1. A list or collection of very few things. Maybe even one thing. Which would make it a non-list.

2. A very long, verbose, and not entirely informative exposition on a body of work.

3. A publication containing one piece of work and one piece of work alone. Which is, technically speaking, what most books are, anyway. So I guess you could say that the typical storybook is somewhat an 'anti-compendium', or an 'expendium' if you choose to employ a word that doesn't exist to describe something that doesn't exist. Appropriate though, wouldn't you say?