[Tarana]

A book can either be the writings of an author or the container where the words are located. In other words, if I refer to the book, Jurassic Park, I am referring to the writings of Michael Crichton as contained in the container of either a paper book, ebook or audiobook AS OPPOSED to the screenplay, which is an adaptation (even if he wrote it, as is the case of some of his works). Audiobooks of today are unabridged, so contain the same words even though those words may be performed. However, the older definition - that of a hardcover or paperback, would still be a noun that describes two of the containers.

I think this is how dictionaries will eventually update their entries. Perhaps modifiers will always be used, but so many already are referring to books for all the formats, I don't think it will be required unless it is condensed or abridged.